diff --git a/crates/red_knot_ide/src/completion.rs b/crates/red_knot_ide/src/completion.rs
new file mode 100644
index 0000000000..275b1fcb1e
--- /dev/null
+++ b/crates/red_knot_ide/src/completion.rs
@@ -0,0 +1,39 @@
+use ruff_db::files::File;
+use ruff_db::parsed::parsed_module;
+use ruff_python_ast::visitor::source_order::SourceOrderVisitor;
+use ruff_python_ast::{AnyNodeRef, Identifier};
+use ruff_text_size::TextSize;
+
+use crate::Db;
+
+pub struct Completion {
+    pub label: String,
+}
+
+pub fn completion(db: &dyn Db, file: File, _offset: TextSize) -> Vec<Completion> {
+    let parsed = parsed_module(db.upcast(), file);
+    identifiers(parsed.syntax().into())
+        .into_iter()
+        .map(|label| Completion { label })
+        .collect()
+}
+
+fn identifiers(node: AnyNodeRef) -> Vec<String> {
+    struct Visitor {
+        identifiers: Vec<String>,
+    }
+
+    impl<'a> SourceOrderVisitor<'a> for Visitor {
+        fn visit_identifier(&mut self, id: &'a Identifier) {
+            self.identifiers.push(id.id.as_str().to_string());
+        }
+    }
+
+    let mut visitor = Visitor {
+        identifiers: vec![],
+    };
+    node.visit_source_order(&mut visitor);
+    visitor.identifiers.sort();
+    visitor.identifiers.dedup();
+    visitor.identifiers
+}
diff --git a/crates/red_knot_ide/src/lib.rs b/crates/red_knot_ide/src/lib.rs
index 48f1145894..a85c0cd1fe 100644
--- a/crates/red_knot_ide/src/lib.rs
+++ b/crates/red_knot_ide/src/lib.rs
@@ -1,3 +1,4 @@
+mod completion;
 mod db;
 mod find_node;
 mod goto;
@@ -5,6 +6,7 @@ mod hover;
 mod inlay_hints;
 mod markup;
 
+pub use completion::completion;
 pub use db::Db;
 pub use goto::goto_type_definition;
 pub use hover::hover;
diff --git a/crates/red_knot_server/src/server.rs b/crates/red_knot_server/src/server.rs
index e57d1f7bbf..3556fec9d4 100644
--- a/crates/red_knot_server/src/server.rs
+++ b/crates/red_knot_server/src/server.rs
@@ -227,6 +227,9 @@ impl Server {
             inlay_hint_provider: Some(lsp_types::OneOf::Right(
                 InlayHintServerCapabilities::Options(InlayHintOptions::default()),
             )),
+            completion_provider: Some(lsp_types::CompletionOptions {
+                ..Default::default()
+            }),
             ..Default::default()
         }
     }
diff --git a/crates/red_knot_server/src/server/api.rs b/crates/red_knot_server/src/server/api.rs
index 478666ea61..5bfc835cc5 100644
--- a/crates/red_knot_server/src/server/api.rs
+++ b/crates/red_knot_server/src/server/api.rs
@@ -36,6 +36,11 @@ pub(super) fn request<'a>(req: server::Request) -> Task<'a> {
         request::InlayHintRequestHandler::METHOD => background_request_task::<
             request::InlayHintRequestHandler,
         >(req, BackgroundSchedule::Worker),
+        request::CompletionRequestHandler::METHOD => background_request_task::<
+            request::CompletionRequestHandler,
+        >(
+            req, BackgroundSchedule::LatencySensitive
+        ),
 
         method => {
             tracing::warn!("Received request {method} which does not have a handler");
diff --git a/crates/red_knot_server/src/server/api/requests.rs b/crates/red_knot_server/src/server/api/requests.rs
index b6e907aa0c..bfdec09623 100644
--- a/crates/red_knot_server/src/server/api/requests.rs
+++ b/crates/red_knot_server/src/server/api/requests.rs
@@ -1,8 +1,10 @@
+mod completion;
 mod diagnostic;
 mod goto_type_definition;
 mod hover;
 mod inlay_hints;
 
+pub(super) use completion::CompletionRequestHandler;
 pub(super) use diagnostic::DocumentDiagnosticRequestHandler;
 pub(super) use goto_type_definition::GotoTypeDefinitionRequestHandler;
 pub(super) use hover::HoverRequestHandler;
diff --git a/crates/red_knot_server/src/server/api/requests/completion.rs b/crates/red_knot_server/src/server/api/requests/completion.rs
new file mode 100644
index 0000000000..93a1c9d8cc
--- /dev/null
+++ b/crates/red_knot_server/src/server/api/requests/completion.rs
@@ -0,0 +1,58 @@
+use std::borrow::Cow;
+
+use lsp_types::request::Completion;
+use lsp_types::{CompletionItem, CompletionParams, CompletionResponse, Url};
+use red_knot_ide::completion;
+use red_knot_project::ProjectDatabase;
+use ruff_db::source::{line_index, source_text};
+
+use crate::document::PositionExt;
+use crate::server::api::traits::{BackgroundDocumentRequestHandler, RequestHandler};
+use crate::server::client::Notifier;
+use crate::DocumentSnapshot;
+
+pub(crate) struct CompletionRequestHandler;
+
+impl RequestHandler for CompletionRequestHandler {
+    type RequestType = Completion;
+}
+
+impl BackgroundDocumentRequestHandler for CompletionRequestHandler {
+    fn document_url(params: &CompletionParams) -> Cow<Url> {
+        Cow::Borrowed(&params.text_document_position.text_document.uri)
+    }
+
+    fn run_with_snapshot(
+        snapshot: DocumentSnapshot,
+        db: ProjectDatabase,
+        _notifier: Notifier,
+        params: CompletionParams,
+    ) -> crate::server::Result<Option<CompletionResponse>> {
+        let Some(file) = snapshot.file(&db) else {
+            tracing::debug!("Failed to resolve file for {:?}", params);
+            return Ok(None);
+        };
+
+        let source = source_text(&db, file);
+        let line_index = line_index(&db, file);
+        let offset = params.text_document_position.position.to_text_size(
+            &source,
+            &line_index,
+            snapshot.encoding(),
+        );
+        let completions = completion(&db, file, offset);
+        if completions.is_empty() {
+            return Ok(None);
+        }
+
+        let items: Vec<CompletionItem> = completions
+            .into_iter()
+            .map(|comp| CompletionItem {
+                label: comp.label,
+                ..Default::default()
+            })
+            .collect();
+        let response = CompletionResponse::Array(items);
+        Ok(Some(response))
+    }
+}
diff --git a/crates/red_knot_server/src/server/schedule/task.rs b/crates/red_knot_server/src/server/schedule/task.rs
index b9ae6f4a59..d269c1edb5 100644
--- a/crates/red_knot_server/src/server/schedule/task.rs
+++ b/crates/red_knot_server/src/server/schedule/task.rs
@@ -21,7 +21,6 @@ pub(in crate::server) enum BackgroundSchedule {
     Fmt,
     /// The task should be run on the general high-priority background
     /// thread. Reserved for actions caused by the user typing (e.g.syntax highlighting).
-    #[expect(dead_code)]
     LatencySensitive,
     /// The task should be run on a regular-priority background thread.
     /// The default for any request that isn't in the critical path of the user typing.