diff --git a/clang-tools-extra/clangd/ClangdLSPServer.h b/clang-tools-extra/clangd/ClangdLSPServer.h
--- a/clang-tools-extra/clangd/ClangdLSPServer.h
+++ b/clang-tools-extra/clangd/ClangdLSPServer.h
@@ -131,6 +131,15 @@
                        Callback<llvm::Optional<TypeHierarchyItem>>);
   void onResolveTypeHierarchy(const ResolveTypeHierarchyItemParams &,
                               Callback<llvm::Optional<TypeHierarchyItem>>);
+  void onPrepareCallHierarchy(
+      const CallHierarchyPrepareParams &,
+      Callback<llvm::Optional<std::vector<CallHierarchyItem>>>);
+  void onCallHierarchyIncomingCalls(
+      const CallHierarchyIncomingCallsParams &,
+      Callback<llvm::Optional<std::vector<CallHierarchyIncomingCall>>>);
+  void onCallHierarchyOutgoingCalls(
+      const CallHierarchyOutgoingCallsParams &,
+      Callback<llvm::Optional<std::vector<CallHierarchyOutgoingCall>>>);
   void onChangeConfiguration(const DidChangeConfigurationParams &);
   void onSymbolInfo(const TextDocumentPositionParams &,
                     Callback<std::vector<SymbolDetails>>);
diff --git a/clang-tools-extra/clangd/ClangdLSPServer.cpp b/clang-tools-extra/clangd/ClangdLSPServer.cpp
--- a/clang-tools-extra/clangd/ClangdLSPServer.cpp
+++ b/clang-tools-extra/clangd/ClangdLSPServer.cpp
@@ -617,6 +617,7 @@
                    ExecuteCommandParams::CLANGD_APPLY_TWEAK}},
              }},
             {"typeHierarchyProvider", true},
+            {"callHierarchyProvider", true},
         }}}};
   if (Opts.Encoding)
     Result["offsetEncoding"] = *Opts.Encoding;
@@ -1208,6 +1209,25 @@
                                std::move(Reply));
 }
 
+void ClangdLSPServer::onPrepareCallHierarchy(
+    const CallHierarchyPrepareParams &Params,
+    Callback<Optional<std::vector<CallHierarchyItem>>> Reply) {
+  Server->prepareCallHierarchy(Params.textDocument.uri.file(), Params.position,
+                               std::move(Reply));
+}
+
+void ClangdLSPServer::onCallHierarchyIncomingCalls(
+    const CallHierarchyIncomingCallsParams &Params,
+    Callback<Optional<std::vector<CallHierarchyIncomingCall>>> Reply) {
+  Server->incomingCalls(Params.Item, std::move(Reply));
+}
+
+void ClangdLSPServer::onCallHierarchyOutgoingCalls(
+    const CallHierarchyOutgoingCallsParams &Params,
+    Callback<Optional<std::vector<CallHierarchyOutgoingCall>>> Reply) {
+  Server->outgoingCalls(Params.Item, std::move(Reply));
+}
+
 void ClangdLSPServer::applyConfiguration(
     const ConfigurationSettings &Settings) {
   // Per-file update to the compilation database.
@@ -1421,6 +1441,9 @@
   MsgHandler->bind("textDocument/symbolInfo", &ClangdLSPServer::onSymbolInfo);
   MsgHandler->bind("textDocument/typeHierarchy", &ClangdLSPServer::onTypeHierarchy);
   MsgHandler->bind("typeHierarchy/resolve", &ClangdLSPServer::onResolveTypeHierarchy);
+  MsgHandler->bind("textDocument/prepareCallHierarchy", &ClangdLSPServer::onPrepareCallHierarchy);
+  MsgHandler->bind("callHierarchy/incomingCalls", &ClangdLSPServer::onCallHierarchyIncomingCalls);
+  MsgHandler->bind("callHierarchy/outgoingCalls", &ClangdLSPServer::onCallHierarchyOutgoingCalls);
   MsgHandler->bind("textDocument/selectionRange", &ClangdLSPServer::onSelectionRange);
   MsgHandler->bind("textDocument/documentLink", &ClangdLSPServer::onDocumentLink);
   MsgHandler->bind("textDocument/semanticTokens/full", &ClangdLSPServer::onSemanticTokens);
diff --git a/clang-tools-extra/clangd/test/call-hierarchy.test b/clang-tools-extra/clangd/test/call-hierarchy.test
new file mode 100644
--- /dev/null
+++ b/clang-tools-extra/clangd/test/call-hierarchy.test
@@ -0,0 +1,88 @@
+# RUN: clangd -lit-test < %s | FileCheck -strict-whitespace %s
+{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{},"trace":"off"}}
+---
+{"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"languageId":"cpp","text":"void callee(int);\nvoid caller1() {\n  callee(42);\n}\nvoid caller2() {\n  caller1();\n  caller1();\n}\nvoid caller3() {\n  caller1();\n  caller2();\n}\n","uri":"test:///main.cpp","version":1}}}
+---
+{"jsonrpc":"2.0","id":1,"method":"textDocument/prepareCallHierarchy","params":{"position":{"character":8,"line":0},"textDocument":{"uri":"test:///main.cpp"}}}
+#      CHECK:  "id": 1,
+# CHECK-NEXT:  "jsonrpc": "2.0",
+# CHECK-NEXT:  "result": [
+# CHECK-NEXT:    {
+# CHECK-NEXT:      "data": "F0E64FE3F8FEA480",
+# CHECK-NEXT:      "detail": "",
+# CHECK-NEXT:      "kind": 12,
+# CHECK-NEXT:      "name": "callee",
+# CHECK-NEXT:      "range": {
+# CHECK-NEXT:        "end": {
+# CHECK-NEXT:          "character": 16,
+# CHECK-NEXT:          "line": 0
+# CHECK-NEXT:        },
+# CHECK-NEXT:        "start": {
+# CHECK-NEXT:          "character": 0,
+# CHECK-NEXT:          "line": 0
+# CHECK-NEXT:        }
+# CHECK-NEXT:      },
+# CHECK-NEXT:      "selectionRange": {
+# CHECK-NEXT:        "end": {
+# CHECK-NEXT:          "character": 11,
+# CHECK-NEXT:          "line": 0
+# CHECK-NEXT:        },
+# CHECK-NEXT:        "start": {
+# CHECK-NEXT:          "character": 5,
+# CHECK-NEXT:          "line": 0
+# CHECK-NEXT:        }
+# CHECK-NEXT:      },
+# CHECK-NEXT:      "tags": [],
+# CHECK-NEXT:      "uri": "file://{{.*}}/clangd-test/main.cpp"
+# CHECK-NEXT:    }
+---
+{"jsonrpc":"2.0","id":2,"method":"callHierarchy/incomingCalls","params":{"item":{"data":"F0E64FE3F8FEA480","kind":12,"name":"callee","range":{"end":{"character":16,"line":0},"start":{"character":0,"line":0}},"selectionRange":{"end":{"character":11,"line":0},"start":{"character":5,"line":0}},"uri":"test:///main.cpp"}}}
+#      CHECK:  "id": 2,
+# CHECK-NEXT:  "jsonrpc": "2.0",
+# CHECK-NEXT:  "result": [
+# CHECK-NEXT:    {
+# CHECK-NEXT:      "from": {
+# CHECK-NEXT:        "data": "3455CD75A68B8B8F",
+# CHECK-NEXT:        "detail": "",
+# CHECK-NEXT:        "kind": 12,
+# CHECK-NEXT:        "name": "caller1",
+# CHECK-NEXT:        "range": {
+# CHECK-NEXT:          "end": {
+# CHECK-NEXT:            "character": 12,
+# CHECK-NEXT:            "line": 1
+# CHECK-NEXT:          },
+# CHECK-NEXT:          "start": {
+# CHECK-NEXT:            "character": 5,
+# CHECK-NEXT:            "line": 1
+# CHECK-NEXT:          }
+# CHECK-NEXT:        },
+# CHECK-NEXT:        "selectionRange": {
+# CHECK-NEXT:          "end": {
+# CHECK-NEXT:            "character": 12,
+# CHECK-NEXT:            "line": 1
+# CHECK-NEXT:          },
+# CHECK-NEXT:          "start": {
+# CHECK-NEXT:            "character": 5,
+# CHECK-NEXT:            "line": 1
+# CHECK-NEXT:          }
+# CHECK-NEXT:        },
+# CHECK-NEXT:        "tags": [],
+# CHECK-NEXT:        "uri": "file:///clangd-test/main.cpp"
+# CHECK-NEXT:      },
+# CHECK-NEXT:      "fromRanges": [
+# CHECK-NEXT:        {
+# CHECK-NEXT:          "end": {
+# CHECK-NEXT:            "character": 8,
+# CHECK-NEXT:            "line": 2
+# CHECK-NEXT:          },
+# CHECK-NEXT:          "start": {
+# CHECK-NEXT:            "character": 2,
+# CHECK-NEXT:            "line": 2
+# CHECK-NEXT:          }
+# CHECK-NEXT:        }
+# CHECK-NEXT:      ]
+# CHECK-NEXT:    }
+---
+{"jsonrpc":"2.0","id":3,"method":"shutdown"}
+---
+{"jsonrpc":"2.0","method":"exit"}
diff --git a/clang-tools-extra/clangd/test/initialize-params.test b/clang-tools-extra/clangd/test/initialize-params.test
--- a/clang-tools-extra/clangd/test/initialize-params.test
+++ b/clang-tools-extra/clangd/test/initialize-params.test
@@ -5,6 +5,7 @@
 # CHECK-NEXT:  "jsonrpc": "2.0",
 # CHECK-NEXT:  "result": {
 # CHECK-NEXT:    "capabilities": {
+# CHECK-NEXT:      "callHierarchyProvider": true,
 # CHECK-NEXT:      "codeActionProvider": true,
 # CHECK-NEXT:      "completionProvider": {
 # CHECK-NEXT:        "allCommitCharacters": [