diff --git a/Cargo.toml b/Cargo.toml
index a28e8e4..55470d1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,7 +15,9 @@ readme = "README.md"
 serde = { version = "1.0", features = ["derive"]}
 serde_json = "1.0"
 chrono = { version = "0.4", features = ["serde"]}
-reqwest = "0.11"
+reqwest = { version = "0.11", features = ["stream"]}
+futures-util = "0.3"
+async-stream = "0.3.3"
 base64 = "0.13"
 
 [features]
diff --git a/src/client.rs b/src/client.rs
index 8954ae7..d700863 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -190,8 +190,8 @@ impl Client {
 mod tests {
     use crate::email::EmailBodyPart;
 
-    #[test]
-    fn test_serialize() {
+    //#[test]
+    fn _test_serialize() {
         println!(
             "{:?}",
             serde_json::from_slice::<EmailBodyPart>(
diff --git a/src/email/mod.rs b/src/email/mod.rs
index 70eeb7f..9593fb1 100644
--- a/src/email/mod.rs
+++ b/src/email/mod.rs
@@ -260,7 +260,7 @@ pub struct EmailHeader<State = Get> {
     value: String,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum Property {
     Id,
     BlobId,
diff --git a/src/email_submission/mod.rs b/src/email_submission/mod.rs
index 635b81b..7fa90a5 100644
--- a/src/email_submission/mod.rs
+++ b/src/email_submission/mod.rs
@@ -127,7 +127,7 @@ pub enum Displayed {
     Yes,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,
diff --git a/src/event_source/mod.rs b/src/event_source/mod.rs
index 9b45ae3..1860794 100644
--- a/src/event_source/mod.rs
+++ b/src/event_source/mod.rs
@@ -1,4 +1,11 @@
-use crate::core::session::URLParser;
+pub mod parser;
+pub mod stream;
+
+use std::collections::HashMap;
+
+use serde::{Deserialize, Serialize};
+
+use crate::{core::session::URLParser, TypeState};
 
 pub enum URLParameter {
     Types,
@@ -16,3 +23,22 @@ impl URLParser for URLParameter {
         }
     }
 }
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Changes {
+    changes: HashMap<String, HashMap<TypeState, String>>,
+}
+
+impl Changes {
+    pub fn account_changes(&mut self, account_id: &str) -> Option<HashMap<TypeState, String>> {
+        self.changes.remove(account_id)
+    }
+
+    pub fn changed_accounts(&self) -> impl Iterator<Item = &String> {
+        self.changes.keys()
+    }
+
+    pub fn into_innter(self) -> HashMap<String, HashMap<TypeState, String>> {
+        self.changes
+    }
+}
diff --git a/src/event_source/parser.rs b/src/event_source/parser.rs
new file mode 100644
index 0000000..ffcd204
--- /dev/null
+++ b/src/event_source/parser.rs
@@ -0,0 +1,292 @@
+use crate::StateChange;
+
+use super::Changes;
+
+const MAX_EVENT_SIZE: usize = 1024 * 1024;
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub enum EventType {
+    Ping,
+    State,
+}
+
+impl Default for EventType {
+    fn default() -> Self {
+        Self::State
+    }
+}
+
+#[derive(Default, Debug)]
+pub struct Event {
+    pub event: EventType,
+    pub id: Vec<u8>,
+    pub data: Vec<u8>,
+}
+
+#[derive(Debug, Copy, Clone)]
+enum EventParserState {
+    Init,
+    Comment,
+    Field,
+    Value,
+}
+
+impl Default for EventParserState {
+    fn default() -> Self {
+        Self::Init
+    }
+}
+
+#[derive(Default, Debug)]
+pub struct EventParser {
+    state: EventParserState,
+    field: Vec<u8>,
+    value: Vec<u8>,
+    bytes: Option<Vec<u8>>,
+    pos: usize,
+    result: Event,
+}
+
+impl EventParser {
+    pub fn push_bytes(&mut self, bytes: Vec<u8>) {
+        self.bytes = Some(bytes);
+    }
+
+    pub fn needs_bytes(&self) -> bool {
+        self.bytes.is_none()
+    }
+
+    pub fn filter_state(&mut self) -> Option<crate::Result<Changes>> {
+        #[allow(clippy::while_let_on_iterator)]
+        while let Some(event) = self.next() {
+            match event {
+                Ok(Event {
+                    event: EventType::State,
+                    data,
+                    ..
+                }) => {
+                    return match serde_json::from_slice::<StateChange>(&data) {
+                        Ok(state_change) => Some(Ok(Changes {
+                            changes: state_change.changed,
+                        })),
+                        Err(err) => Some(Err(err.into())),
+                    };
+                }
+                Ok(Event {
+                    event: EventType::Ping,
+                    ..
+                }) => {
+                    #[cfg(feature = "debug")]
+                    use std::iter::FromIterator;
+                    #[cfg(feature = "debug")]
+                    return Some(Ok(Changes {
+                        changes: std::collections::HashMap::from_iter([(
+                            "ping".to_string(),
+                            std::collections::HashMap::new(),
+                        )]),
+                    }));
+                }
+                Err(err) => return Some(Err(err)),
+            }
+        }
+        None
+    }
+}
+
+impl Iterator for EventParser {
+    type Item = crate::Result<Event>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let bytes = self.bytes.as_ref()?;
+
+        for byte in bytes.get(self.pos..)? {
+            self.pos += 1;
+
+            match self.state {
+                EventParserState::Init => match byte {
+                    b':' => {
+                        self.state = EventParserState::Comment;
+                    }
+                    b'\r' | b' ' => (),
+                    b'\n' => {
+                        return Some(Ok(std::mem::take(&mut self.result)));
+                    }
+                    _ => {
+                        self.state = EventParserState::Field;
+                        self.field.push(*byte);
+                    }
+                },
+                EventParserState::Comment => {
+                    if *byte == b'\n' {
+                        self.state = EventParserState::Init;
+                    }
+                }
+                EventParserState::Field => match byte {
+                    b'\r' => (),
+                    b'\n' => {
+                        self.state = EventParserState::Init;
+                        self.field.clear();
+                    }
+                    b':' => {
+                        self.state = EventParserState::Value;
+                    }
+                    _ => {
+                        if self.field.len() >= MAX_EVENT_SIZE {
+                            return Some(Err(crate::Error::Internal(
+                                "EventSource response is too long.".to_string(),
+                            )));
+                        }
+
+                        self.field.push(*byte);
+                    }
+                },
+                EventParserState::Value => match byte {
+                    b'\r' => (),
+                    b' ' if self.value.is_empty() => (),
+                    b'\n' => {
+                        self.state = EventParserState::Init;
+                        match &self.field[..] {
+                            b"id" => {
+                                self.result.id.extend_from_slice(&self.value);
+                            }
+                            b"data" => {
+                                self.result.data.extend_from_slice(&self.value);
+                            }
+                            b"event" => {
+                                if self.value == b"ping" {
+                                    self.result.event = EventType::Ping;
+                                } else {
+                                    self.result.event = EventType::State;
+                                }
+                            }
+                            _ => {
+                                //ignore
+                            }
+                        }
+                        self.field.clear();
+                        self.value.clear();
+                    }
+                    _ => {
+                        if (self.field.len() + self.value.len()) >= MAX_EVENT_SIZE {
+                            return Some(Err(crate::Error::Internal(
+                                "EventSource response is too long.".to_string(),
+                            )));
+                        }
+
+                        self.value.push(*byte);
+                    }
+                },
+            }
+        }
+
+        self.bytes = None;
+        self.pos = 0;
+
+        None
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::{Event, EventType};
+
+    #[derive(Debug, PartialEq, Eq)]
+    struct EventString {
+        event: EventType,
+        id: String,
+        data: String,
+    }
+
+    impl From<Event> for EventString {
+        fn from(event: Event) -> Self {
+            Self {
+                event: event.event,
+                id: String::from_utf8(event.id).unwrap(),
+                data: String::from_utf8(event.data).unwrap(),
+            }
+        }
+    }
+
+    #[test]
+    fn parse() {
+        let mut parser = super::EventParser::default();
+        let mut results = Vec::new();
+
+        for frame in [
+            Vec::from("event: state\nid:  0\ndata: test\n\n"),
+            Vec::from("event: ping\nid:123\ndata: ping pa"),
+            Vec::from("yload"),
+            Vec::from("\n\n"),
+            Vec::from(":comment\n\n"),
+            Vec::from("data: YHOO\n"),
+            Vec::from("data: +2\n"),
+            Vec::from("data: 10\n\n"),
+            Vec::from(": test stream\n"),
+            Vec::from("data: first event\n"),
+            Vec::from("id: 1\n\n"),
+            Vec::from("data:second event\n"),
+            Vec::from("id\n\n"),
+            Vec::from("data:  third event\n\n"),
+            Vec::from("data:hello\n\ndata: world\n\n"),
+        ] {
+            parser.push_bytes(frame);
+
+            #[allow(clippy::while_let_on_iterator)]
+            while let Some(event) = parser.next() {
+                results.push(EventString::from(event.unwrap()));
+            }
+        }
+
+        assert_eq!(
+            results,
+            vec![
+                EventString {
+                    event: EventType::State,
+                    id: "0".to_string(),
+                    data: "test".to_string()
+                },
+                EventString {
+                    event: EventType::Ping,
+                    id: "123".to_string(),
+                    data: "ping payload".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "YHOO+210".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "1".to_string(),
+                    data: "first event".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "second event".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "third event".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "hello".to_string()
+                },
+                EventString {
+                    event: EventType::State,
+                    id: "".to_string(),
+                    data: "world".to_string()
+                }
+            ]
+        );
+    }
+}
diff --git a/src/event_source/stream.rs b/src/event_source/stream.rs
new file mode 100644
index 0000000..5c1f179
--- /dev/null
+++ b/src/event_source/stream.rs
@@ -0,0 +1,101 @@
+use std::time::Duration;
+
+use crate::{client::Client, core::session::URLPart, event_source::parser::EventParser, TypeState};
+use async_stream::stream;
+use futures_util::{Stream, StreamExt};
+use reqwest::header::{HeaderValue, ACCEPT, CONTENT_TYPE};
+
+use super::Changes;
+
+impl Client {
+    pub async fn event_source(
+        &mut self,
+        mut types: Option<impl IntoIterator<Item = TypeState>>,
+        close_after_state: bool,
+        ping: Option<u32>,
+        last_event_id: Option<&str>,
+    ) -> crate::Result<impl Stream<Item = crate::Result<Changes>>> {
+        let mut event_source_url = String::with_capacity(self.session().event_source_url().len());
+
+        for part in self.event_source_url() {
+            match part {
+                URLPart::Value(value) => {
+                    event_source_url.push_str(value);
+                }
+                URLPart::Parameter(param) => match param {
+                    super::URLParameter::Types => {
+                        if let Some(types) = Option::take(&mut types) {
+                            event_source_url.push_str(
+                                &types
+                                    .into_iter()
+                                    .map(|state| state.to_string())
+                                    .collect::<Vec<_>>()
+                                    .join(","),
+                            );
+                        } else {
+                            event_source_url.push('*');
+                        }
+                    }
+                    super::URLParameter::CloseAfter => {
+                        event_source_url.push_str(if close_after_state { "state" } else { "no" });
+                    }
+                    super::URLParameter::Ping => {
+                        if let Some(ping) = ping {
+                            event_source_url.push_str(&ping.to_string());
+                        } else {
+                            event_source_url.push('0');
+                        }
+                    }
+                },
+            }
+        }
+
+        // Add headers
+        let mut headers = self.headers().clone();
+        headers.remove(CONTENT_TYPE);
+        headers.insert(ACCEPT, HeaderValue::from_static("text/event-stream"));
+        if let Some(last_event_id) = last_event_id {
+            headers.insert(
+                "Last-Event-ID",
+                HeaderValue::from_str(last_event_id).unwrap(),
+            );
+        }
+
+        let mut stream = Client::handle_error(
+            reqwest::Client::builder()
+                .timeout(Duration::from_millis(self.timeout()))
+                .default_headers(headers)
+                .build()?
+                .get(event_source_url)
+                .send()
+                .await?,
+        )
+        .await?
+        .bytes_stream();
+        let mut parser = EventParser::default();
+
+        // TODO - use poll_next() to avoid pin_mut() call.
+        Ok(stream! {
+            loop {
+                if let Some(changes) = parser.filter_state() {
+                    yield changes;
+                    continue;
+                }
+                if let Some(result) = stream.next().await {
+                    match result {
+                        Ok(bytes) => {
+                            parser.push_bytes(bytes.to_vec());
+                            continue;
+                        }
+                        Err(err) => {
+                            yield Err(err.into());
+                            break;
+                        }
+                    }
+                } else {
+                    break;
+                }
+            }
+        })
+    }
+}
diff --git a/src/identity/mod.rs b/src/identity/mod.rs
index 3983b0b..fa5c4cc 100644
--- a/src/identity/mod.rs
+++ b/src/identity/mod.rs
@@ -49,7 +49,7 @@ pub struct Identity<State = Get> {
     pub may_delete: Option<bool>,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,
diff --git a/src/lib.rs b/src/lib.rs
index 706f50b..bb68d72 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -17,6 +17,8 @@ pub mod push_subscription;
 pub mod thread;
 pub mod vacation_response;
 
+pub use futures_util;
+
 #[derive(Debug, Clone, Serialize, Deserialize, Hash, PartialEq, Eq)]
 pub enum URI {
     #[serde(rename = "urn:ietf:params:jmap:core")]
@@ -100,17 +102,13 @@ pub enum Method {
 }
 
 #[derive(Debug, Serialize, Deserialize, Eq, PartialEq, Hash, Clone)]
-pub enum Object {
-    Core,
+pub enum TypeState {
     Mailbox,
     Thread,
     Email,
     EmailDelivery,
-    SearchSnippet,
     Identity,
     EmailSubmission,
-    VacationResponse,
-    PushSubscription,
 }
 
 #[derive(Deserialize)]
@@ -120,9 +118,9 @@ pub enum StateChangeType {
 
 #[derive(Deserialize)]
 pub struct StateChange {
-    #[serde(rename(serialize = "@type"))]
+    #[serde(rename = "@type")]
     pub type_: StateChangeType,
-    pub changed: HashMap<String, HashMap<Object, String>>,
+    pub changed: HashMap<String, HashMap<TypeState, String>>,
 }
 
 #[derive(Debug, Clone)]
@@ -186,3 +184,16 @@ impl Display for Error {
         }
     }
 }
+
+impl Display for TypeState {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            TypeState::Mailbox => write!(f, "Mailbox"),
+            TypeState::Thread => write!(f, "Thread"),
+            TypeState::Email => write!(f, "Email"),
+            TypeState::EmailDelivery => write!(f, "EmailDelivery"),
+            TypeState::Identity => write!(f, "Identity"),
+            TypeState::EmailSubmission => write!(f, "EmailSubmission"),
+        }
+    }
+}
diff --git a/src/mailbox/helpers.rs b/src/mailbox/helpers.rs
index dd76d4d..3325f66 100644
--- a/src/mailbox/helpers.rs
+++ b/src/mailbox/helpers.rs
@@ -120,7 +120,7 @@ impl Client {
     pub async fn mailbox_query(
         &mut self,
         filter: Option<impl Into<Filter<super::query::Filter>>>,
-        sort: Option<Vec<Comparator<super::query::Comparator>>>,
+        sort: Option<impl IntoIterator<Item = Comparator<super::query::Comparator>>>,
     ) -> crate::Result<QueryResponse> {
         let mut request = self.build();
         let query_request = request.query_mailbox();
@@ -132,6 +132,18 @@ impl Client {
         }
         request.send_single::<QueryResponse>().await
     }
+
+    pub async fn mailbox_changes(
+        &mut self,
+        since_state: impl Into<String>,
+        max_changes: usize,
+    ) -> crate::Result<ChangesResponse<super::ChangesResponse>> {
+        let mut request = self.build();
+        request
+            .changes_mailbox(since_state)
+            .max_changes(max_changes);
+        request.send_single().await
+    }
 }
 
 impl Request<'_> {
diff --git a/src/mailbox/mod.rs b/src/mailbox/mod.rs
index 3ca9693..f72b593 100644
--- a/src/mailbox/mod.rs
+++ b/src/mailbox/mod.rs
@@ -87,12 +87,19 @@ pub struct Mailbox<State = Get> {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "lowercase")]
 pub enum Role {
+    #[serde(rename = "archive", alias = "ARCHIVE")]
     Archive,
+    #[serde(rename = "drafts", alias = "DRAFTS")]
     Drafts,
+    #[serde(rename = "importante", alias = "IMPORTANT")]
     Important,
+    #[serde(rename = "inbox", alias = "INBOX")]
     Inbox,
+    #[serde(rename = "junk", alias = "JUNK")]
     Junk,
+    #[serde(rename = "sent", alias = "SENT")]
     Sent,
+    #[serde(rename = "trash", alias = "TRASH")]
     Trash,
     None,
 }
@@ -127,7 +134,7 @@ pub struct MailboxRights {
     may_submit: bool,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,
diff --git a/src/mailbox/query.rs b/src/mailbox/query.rs
index df39e22..fdecd56 100644
--- a/src/mailbox/query.rs
+++ b/src/mailbox/query.rs
@@ -41,12 +41,16 @@ pub enum Comparator {
 }
 
 impl Filter {
-    pub fn parent_id(value: Option<String>) -> Self {
-        Filter::ParentId { value }
+    pub fn parent_id(value: Option<impl Into<String>>) -> Self {
+        Filter::ParentId {
+            value: value.map(Into::into),
+        }
     }
 
-    pub fn name(value: String) -> Self {
-        Filter::Name { value }
+    pub fn name(value: impl Into<String>) -> Self {
+        Filter::Name {
+            value: value.into(),
+        }
     }
 
     pub fn role(value: Role) -> Self {
diff --git a/src/mailbox/set.rs b/src/mailbox/set.rs
index 094a8be..21e274c 100644
--- a/src/mailbox/set.rs
+++ b/src/mailbox/set.rs
@@ -13,6 +13,11 @@ impl Mailbox<Set> {
         self
     }
 
+    pub fn parent_id_ref(&mut self, parent_id_ref: &str) -> &mut Self {
+        self.parent_id = format!("#{}", parent_id_ref).into();
+        self
+    }
+
     pub fn role(&mut self, role: Role) -> &mut Self {
         if !matches!(role, Role::None) {
             self.role = Some(role);
diff --git a/src/push_subscription/get.rs b/src/push_subscription/get.rs
index d3d39ac..8ff90c3 100644
--- a/src/push_subscription/get.rs
+++ b/src/push_subscription/get.rs
@@ -1,4 +1,4 @@
-use crate::{Get, Object};
+use crate::{Get, TypeState};
 
 use super::{Keys, PushSubscription};
 
@@ -27,7 +27,7 @@ impl PushSubscription<Get> {
         self.expires.map(|v| v.timestamp())
     }
 
-    pub fn types(&self) -> Option<&[Object]> {
+    pub fn types(&self) -> Option<&[TypeState]> {
         self.types.as_deref()
     }
 }
diff --git a/src/push_subscription/mod.rs b/src/push_subscription/mod.rs
index 8c8d78b..f7a2380 100644
--- a/src/push_subscription/mod.rs
+++ b/src/push_subscription/mod.rs
@@ -8,7 +8,7 @@ use chrono::{DateTime, Utc};
 use serde::{Deserialize, Serialize};
 
 use crate::core::set::list_not_set;
-use crate::{Get, Object};
+use crate::{Get, TypeState};
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct PushSubscription<State = Get> {
@@ -44,10 +44,10 @@ pub struct PushSubscription<State = Get> {
 
     #[serde(rename = "types")]
     #[serde(skip_serializing_if = "list_not_set")]
-    types: Option<Vec<Object>>,
+    types: Option<Vec<TypeState>>,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,
diff --git a/src/push_subscription/set.rs b/src/push_subscription/set.rs
index 0cc0347..44e1154 100644
--- a/src/push_subscription/set.rs
+++ b/src/push_subscription/set.rs
@@ -1,6 +1,6 @@
 use crate::{
     core::set::{from_timestamp, Create},
-    Object, Set,
+    Set, TypeState,
 };
 
 use super::{Keys, PushSubscription};
@@ -31,7 +31,7 @@ impl PushSubscription<Set> {
         self
     }
 
-    pub fn types(&mut self, types: Option<impl Iterator<Item = Object>>) -> &mut Self {
+    pub fn types(&mut self, types: Option<impl Iterator<Item = TypeState>>) -> &mut Self {
         self.types = types.map(|s| s.collect());
         self
     }
diff --git a/src/thread/mod.rs b/src/thread/mod.rs
index a2cd68c..5a76957 100644
--- a/src/thread/mod.rs
+++ b/src/thread/mod.rs
@@ -12,7 +12,7 @@ pub struct Thread {
     email_ids: Vec<String>,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,
diff --git a/src/vacation_response/mod.rs b/src/vacation_response/mod.rs
index 4e3a920..7e14707 100644
--- a/src/vacation_response/mod.rs
+++ b/src/vacation_response/mod.rs
@@ -47,7 +47,7 @@ pub struct VacationResponse<State = Get> {
     html_body: Option<String>,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Copy)]
 pub enum Property {
     #[serde(rename = "id")]
     Id,