diff --git a/go/ql/lib/semmle/go/dataflow/internal/DataFlowDispatch.qll b/go/ql/lib/semmle/go/dataflow/internal/DataFlowDispatch.qll
index 2c7e3356f3c2..af1df52113dd 100644
--- a/go/ql/lib/semmle/go/dataflow/internal/DataFlowDispatch.qll
+++ b/go/ql/lib/semmle/go/dataflow/internal/DataFlowDispatch.qll
@@ -51,6 +51,12 @@ private predicate isConcreteInterfaceCall(DataFlow::Node call, DataFlow::Node re
   isInterfaceCallReceiver(call, recv, _, m) and isConcreteValue(recv)
 }
 
+private Function getRealOrSummarizedFunction(DataFlowCallable c) {
+  result = c.asCallable().asFunction()
+  or
+  result = c.asSummarizedCallable().asFunction()
+}
+
 /**
  * Gets a function that might be called by `call`, where the receiver of `call` has interface type,
  * but its concrete types can be determined by local reasoning.
@@ -59,7 +65,7 @@ private DataFlowCallable getConcreteTarget(DataFlow::CallNode call) {
   exists(string m | isConcreteInterfaceCall(call, _, m) |
     exists(Type concreteReceiverType |
       concreteReceiverType = getConcreteType(getInterfaceCallReceiverSource(call)) and
-      result.asFunction() = concreteReceiverType.getMethod(m)
+      getRealOrSummarizedFunction(result) = concreteReceiverType.getMethod(m)
     )
   )
 }
@@ -78,7 +84,7 @@ private predicate isInterfaceMethodCall(DataFlow::CallNode call) {
 private DataFlowCallable getRestrictedInterfaceTarget(DataFlow::CallNode call) {
   exists(InterfaceType tp, Type recvtp, string m |
     isInterfaceCallReceiver(call, _, tp, m) and
-    result.asFunction() = recvtp.getMethod(m) and
+    getRealOrSummarizedFunction(result) = recvtp.getMethod(m) and
     recvtp.implements(tp)
   )
 }
@@ -93,7 +99,8 @@ DataFlowCallable viableCallable(CallExpr ma) {
     else
       if isInterfaceMethodCall(call)
       then result = getRestrictedInterfaceTarget(call)
-      else result.asCallable() = call.getACalleeIncludingExternals()
+      else
+        [result.asCallable(), result.asSummarizedCallable()] = call.getACalleeIncludingExternals()
   )
 }
 
diff --git a/go/ql/lib/semmle/go/dataflow/internal/DataFlowNodes.qll b/go/ql/lib/semmle/go/dataflow/internal/DataFlowNodes.qll
index 715330f87d9f..7e92b3eb1fe2 100644
--- a/go/ql/lib/semmle/go/dataflow/internal/DataFlowNodes.qll
+++ b/go/ql/lib/semmle/go/dataflow/internal/DataFlowNodes.qll
@@ -10,14 +10,8 @@ private newtype TNode =
   MkInstructionNode(IR::Instruction insn) or
   MkSsaNode(SsaDefinition ssa) or
   MkGlobalFunctionNode(Function f) or
-  MkSummarizedParameterNode(DataFlowCallable c, int i) {
-    not exists(c.getFuncDef()) and
-    c.asCallable() instanceof SummarizedCallable and
-    (
-      i in [0 .. c.getType().getNumParameter() - 1]
-      or
-      c.asFunction() instanceof Method and i = -1
-    )
+  MkSummarizedParameterNode(SummarizedCallable c, int i) {
+    FlowSummaryImpl::Private::summaryParameterNodeRange(c, i)
   } or
   MkSummaryInternalNode(SummarizedCallable c, FlowSummaryImpl::Private::SummaryNodeState state) {
     FlowSummaryImpl::Private::summaryNodeRange(c, state)
@@ -31,12 +25,18 @@ module Private {
   DataFlowCallable nodeGetEnclosingCallable(Node n) {
     result.asCallable() = n.getEnclosingCallable()
     or
-    not exists(n.getEnclosingCallable()) and result.asFileScope() = n.getFile()
+    (n = MkInstructionNode(_) or n = MkSsaNode(_) or n = MkGlobalFunctionNode(_)) and
+    not exists(n.getEnclosingCallable()) and
+    result.asFileScope() = n.getFile()
+    or
+    n = MkSummarizedParameterNode(result.asSummarizedCallable(), _)
+    or
+    n = MkSummaryInternalNode(result.asSummarizedCallable(), _)
   }
 
   /** Holds if `p` is a `ParameterNode` of `c` with position `pos`. */
   predicate isParameterNode(ParameterNode p, DataFlowCallable c, ParameterPosition pos) {
-    p.isParameterOf(c.asCallable(), pos)
+    p.isParameterOf(c, pos)
   }
 
   /** Holds if `arg` is an `ArgumentNode` of `c` with position `pos`. */
@@ -116,15 +116,7 @@ module Public {
     ControlFlow::Root getRoot() { none() } // overridden in subclasses
 
     /** INTERNAL: Use `getRoot()` instead. */
-    Callable getEnclosingCallable() {
-      result.getFuncDef() = this.getRoot()
-      or
-      exists(DataFlowCallable dfc | result = dfc.asCallable() |
-        this = MkSummarizedParameterNode(dfc, _)
-        or
-        this = MkSummaryInternalNode(dfc.asCallable(), _)
-      )
-    }
+    Callable getEnclosingCallable() { result.getFuncDef() = this.getRoot() }
 
     /** Gets the type of this node. */
     Type getType() { none() } // overridden in subclasses
@@ -578,7 +570,7 @@ module Public {
   /** A representation of a parameter initialization. */
   abstract class ParameterNode extends DataFlow::Node {
     /** Holds if this node initializes the `i`th parameter of `c`. */
-    abstract predicate isParameterOf(Callable c, int i);
+    abstract predicate isParameterOf(DataFlowCallable c, int i);
   }
 
   /**
@@ -586,12 +578,10 @@ module Public {
    * already have a parameter nodes.
    */
   class SummarizedParameterNode extends ParameterNode, MkSummarizedParameterNode {
-    Callable c;
+    SummarizedCallable c;
     int i;
 
-    SummarizedParameterNode() {
-      this = MkSummarizedParameterNode(any(DataFlowCallable dfc | c = dfc.asCallable()), i)
-    }
+    SummarizedParameterNode() { this = MkSummarizedParameterNode(c, i) }
 
     // There are no AST representations of summarized parameter nodes
     override ControlFlow::Root getRoot() { none() }
@@ -604,7 +594,9 @@ module Public {
       i = -1 and result = c.asFunction().(Method).getReceiverType()
     }
 
-    override predicate isParameterOf(Callable call, int idx) { c = call and i = idx }
+    override predicate isParameterOf(DataFlowCallable call, int idx) {
+      c = call.asSummarizedCallable() and i = idx
+    }
 
     override string toString() { result = "parameter " + i + " of " + c.toString() }
 
@@ -623,7 +615,9 @@ module Public {
     /** Gets the parameter this node initializes. */
     override Parameter asParameter() { result = parm }
 
-    override predicate isParameterOf(Callable c, int i) { parm.isParameterOf(c.getFuncDef(), i) }
+    override predicate isParameterOf(DataFlowCallable c, int i) {
+      parm.isParameterOf(c.asCallable().getFuncDef(), i)
+    }
   }
 
   /** A representation of a receiver initialization. */
diff --git a/go/ql/lib/semmle/go/dataflow/internal/DataFlowPrivate.qll b/go/ql/lib/semmle/go/dataflow/internal/DataFlowPrivate.qll
index d57adbe5d693..566951bf75be 100644
--- a/go/ql/lib/semmle/go/dataflow/internal/DataFlowPrivate.qll
+++ b/go/ql/lib/semmle/go/dataflow/internal/DataFlowPrivate.qll
@@ -3,6 +3,7 @@ private import DataFlowUtil
 private import DataFlowImplCommon
 private import ContainerFlow
 private import FlowSummaryImpl as FlowSummaryImpl
+private import semmle.go.dataflow.FlowSummary as FlowSummary
 import codeql.util.Unit
 import DataFlowNodes::Private
 
@@ -237,31 +238,31 @@ class DataFlowLocation = Location;
 
 private newtype TDataFlowCallable =
   TCallable(Callable c) or
-  TFileScope(File f)
+  TFileScope(File f) or
+  TSummarizedCallable(FlowSummary::SummarizedCallable c)
 
 class DataFlowCallable extends TDataFlowCallable {
   Callable asCallable() { this = TCallable(result) }
 
   File asFileScope() { this = TFileScope(result) }
 
-  FuncDef getFuncDef() { result = this.asCallable().getFuncDef() }
+  FlowSummary::SummarizedCallable asSummarizedCallable() { this = TSummarizedCallable(result) }
 
-  Function asFunction() { result = this.asCallable().asFunction() }
-
-  FuncLit asFuncLit() { result = this.asCallable().asFuncLit() }
-
-  SignatureType getType() { result = this.asCallable().getType() }
+  SignatureType getType() { result = [this.asCallable(), this.asSummarizedCallable()].getType() }
 
   string toString() {
     result = this.asCallable().toString() or
-    result = "File scope: " + this.asFileScope().toString()
+    result = "File scope: " + this.asFileScope().toString() or
+    result = "Summary: " + this.asSummarizedCallable().toString()
   }
 
   predicate hasLocationInfo(
     string filepath, int startline, int startcolumn, int endline, int endcolumn
   ) {
     this.asCallable().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) or
-    this.asFileScope().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
+    this.asFileScope().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) or
+    this.asSummarizedCallable()
+        .hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
   }
 }
 
@@ -281,6 +282,7 @@ class DataFlowCall extends Expr {
 
   /** Gets the enclosing callable of this call. */
   DataFlowCallable getEnclosingCallable() {
+    // NB. At present calls cannot occur inside summarized callables-- this will change if we implement advanced lambda support.
     result.asCallable().getFuncDef() = this.getEnclosingFunction()
     or
     not exists(this.getEnclosingFunction()) and result.asFileScope() = this.getFile()
diff --git a/go/ql/lib/semmle/go/dataflow/internal/FlowSummaryImplSpecific.qll b/go/ql/lib/semmle/go/dataflow/internal/FlowSummaryImplSpecific.qll
index 7eedf1f911ec..7d84e645b666 100644
--- a/go/ql/lib/semmle/go/dataflow/internal/FlowSummaryImplSpecific.qll
+++ b/go/ql/lib/semmle/go/dataflow/internal/FlowSummaryImplSpecific.qll
@@ -17,7 +17,7 @@ private module FlowSummaries {
 
 class SummarizedCallableBase = Callable;
 
-DataFlowCallable inject(SummarizedCallable c) { result.asCallable() = c }
+DataFlowCallable inject(SummarizedCallable c) { result.asSummarizedCallable() = c }
 
 /** Gets the parameter position of the instance parameter. */
 ArgumentPosition callbackSelfParameterPosition() { result = -1 }
@@ -189,9 +189,7 @@ class InterpretNode extends TInterpretNode {
 
   /** Gets the callable that this node corresponds to, if any. */
   DataFlowCallable asCallable() {
-    result.asFunction() = this.asElement().asEntity()
-    or
-    result.asFuncLit() = this.asElement().asAstNode()
+    result.asSummarizedCallable().asFunction() = this.asElement().asEntity()
   }
 
   /** Gets the target of this call, if any. */
diff --git a/go/ql/lib/semmle/go/frameworks/Twirp.qll b/go/ql/lib/semmle/go/frameworks/Twirp.qll
index 047280bc48a9..c4fc0737ac14 100644
--- a/go/ql/lib/semmle/go/frameworks/Twirp.qll
+++ b/go/ql/lib/semmle/go/frameworks/Twirp.qll
@@ -165,8 +165,8 @@ module Twirp {
    */
   class Request extends UntrustedFlowSource::Range instanceof DataFlow::ParameterNode {
     Request() {
-      exists(Callable c, ServiceHandler handler | c.asFunction() = handler |
-        this.isParameterOf(c, 1) and
+      exists(FuncDef c, ServiceHandler handler | handler.getFuncDecl() = c |
+        this.asParameter().isParameterOf(c, 1) and
         handler.getParameterType(0).hasQualifiedName("context", "Context") and
         this.getType().(PointerType).getBaseType() instanceof ProtobufMessageType
       )
diff --git a/go/ql/test/library-tests/semmle/go/dataflow/CallGraph/viableCallee.ql b/go/ql/test/library-tests/semmle/go/dataflow/CallGraph/viableCallee.ql
index e258145d2d16..5c157e7fffa1 100644
--- a/go/ql/test/library-tests/semmle/go/dataflow/CallGraph/viableCallee.ql
+++ b/go/ql/test/library-tests/semmle/go/dataflow/CallGraph/viableCallee.ql
@@ -17,10 +17,10 @@ string metadata(Locatable l, string key) {
 
 query predicate missingCallee(DataFlow::CallNode call, FuncDef callee) {
   metadata(call.asExpr(), "callee") = metadata(callee, "name") and
-  not viableCallable(call.asExpr()).getFuncDef() = callee
+  not viableCallable(call.asExpr()).asCallable().getFuncDef() = callee
 }
 
 query predicate spuriousCallee(DataFlow::CallNode call, FuncDef callee) {
-  viableCallable(call.asExpr()).getFuncDef() = callee and
+  viableCallable(call.asExpr()).asCallable().getFuncDef() = callee and
   not metadata(call.asExpr(), "callee") = metadata(callee, "name")
 }