diff --git a/clang/include/clang/Tooling/Syntax/Nodes.h b/clang/include/clang/Tooling/Syntax/Nodes.h
--- a/clang/include/clang/Tooling/Syntax/Nodes.h
+++ b/clang/include/clang/Tooling/Syntax/Nodes.h
@@ -142,6 +142,8 @@
   /// statement, e.g. loop body for while, for, etc; inner statement for case,
   /// default, etc.
   BodyStatement,
+  List_element,
+  List_delimiter,
 
   // Roles specific to particular node kinds.
   OperatorExpression_operatorToken,
diff --git a/clang/include/clang/Tooling/Syntax/Tree.h b/clang/include/clang/Tooling/Syntax/Tree.h
--- a/clang/include/clang/Tooling/Syntax/Tree.h
+++ b/clang/include/clang/Tooling/Syntax/Tree.h
@@ -191,6 +191,68 @@
   Node *FirstChild = nullptr;
 };
 
+/// A Tree that represents a syntactic list of elements.
+///
+/// We try to model with this type the artificial grammar-construct:
+/// delimited-list(element, delimiter, termination, canBeEmpty)
+///
+/// For example, from C++ [dcl.decl]:
+/// init-declarator-list:
+///   init-declarator
+///   init-declarator-list , init-declarator
+/// May be mapped to:
+///   delimited-list(init-declarator, ',', separated, !canBeEmpty)
+///
+/// Thus the `InitDeclaratorList` syntax node would inherit from `List`, with:
+/// getTerminationKind() returning `Separated`
+/// canBeEmpty() returning `true`
+/// getDelimiterTokenKind() returning `,`
+class List : public Tree {
+  template <typename Element> struct ElementAndDelimiter {
+    Element *element;
+    Leaf *delimiter;
+  };
+
+  enum class TerminationKind {
+    Terminated,
+    MaybeTerminated,
+    Separated,
+  };
+
+  /// Returns the elements and corresponding delimiters. Missing elements
+  /// and delimiters are represented as null pointers.
+  ///
+  /// For example, in a separated list:
+  /// "a, b, c" <=> [("a", ","), ("b", ","), ("c", null)]
+  /// "a, , c" <=> [("a", ","), (null, ","), ("c", ",)]
+  /// "a, b," <=> [("a", ","), ("b", ","), (null, null)]
+  ///
+  /// In a terminated or maybe-terminated list:
+  /// "a, b," <=> [("a", ","), ("b", ",")]
+  std::vector<ElementAndDelimiter<Node>> getElementsAsNodesAndDelimiters();
+
+  /// Returns the elements of the list. Missing elements are represented
+  /// as null pointers in the same way as in the return value of
+  /// `getElementsAsNodesAndDelimiters()`.
+  std::vector<Node *> getElementsAsNodes();
+
+  // These can't be implemented with the information we have!
+
+  /// Returns the appropriate delimiter for this list.
+  ///
+  /// Useful for discovering the correct delimiter to use when adding
+  /// elements to empty or one-element lists.
+  clang::tok::TokenKind getDelimiterTokenKind();
+
+  TerminationKind getTerminationKind();
+
+  /// Return whether *under valid code* the list can be empty.
+  ///
+  /// If the underlying source code is not expected to be valid, then the list
+  /// may be empty even if canBeEmpty() returns false.
+  bool canBeEmpty();
+};
+
 } // namespace syntax
 } // namespace clang
 
diff --git a/clang/lib/Tooling/Syntax/Nodes.cpp b/clang/lib/Tooling/Syntax/Nodes.cpp
--- a/clang/lib/Tooling/Syntax/Nodes.cpp
+++ b/clang/lib/Tooling/Syntax/Nodes.cpp
@@ -144,6 +144,10 @@
     return OS << "ExternKeyword";
   case syntax::NodeRole::BodyStatement:
     return OS << "BodyStatement";
+  case syntax::NodeRole::List_element:
+    return OS << "List_element";
+  case syntax::NodeRole::List_delimiter:
+    return OS << "List_delimiter";
   case syntax::NodeRole::CaseStatement_value:
     return OS << "CaseStatement_value";
   case syntax::NodeRole::IfStatement_thenStatement:
diff --git a/clang/lib/Tooling/Syntax/Tree.cpp b/clang/lib/Tooling/Syntax/Tree.cpp
--- a/clang/lib/Tooling/Syntax/Tree.cpp
+++ b/clang/lib/Tooling/Syntax/Tree.cpp
@@ -270,3 +270,107 @@
   }
   return nullptr;
 }
+
+std::vector<syntax::List::ElementAndDelimiter<syntax::Node>>
+syntax::List::getElementsAsNodesAndDelimiters() {
+  if (!firstChild())
+    return {};
+
+  auto children = std::vector<syntax::List::ElementAndDelimiter<Node>>();
+  syntax::Node *elementWithoutDelimiter = nullptr;
+  for (auto *C = firstChild(); C; C = C->nextSibling()) {
+    switch (C->role()) {
+    case syntax::NodeRole::List_element: {
+      if (elementWithoutDelimiter) {
+        children.push_back({elementWithoutDelimiter, nullptr});
+      }
+      elementWithoutDelimiter = C;
+      break;
+    }
+    case syntax::NodeRole::List_delimiter: {
+      children.push_back({elementWithoutDelimiter, cast<syntax::Leaf>(C)});
+      elementWithoutDelimiter = nullptr;
+      break;
+    }
+    default:
+      llvm_unreachable(
+          "A list can have only elements and delimiters as children.");
+    }
+  }
+
+  switch (getTerminationKind()) {
+  case syntax::List::TerminationKind::Separated: {
+    children.push_back({elementWithoutDelimiter, nullptr});
+    break;
+  }
+  case syntax::List::TerminationKind::Terminated:
+  case syntax::List::TerminationKind::MaybeTerminated: {
+    if (elementWithoutDelimiter) {
+      children.push_back({elementWithoutDelimiter, nullptr});
+    }
+    break;
+  }
+  }
+
+  return children;
+}
+
+// Almost the same implementation of `getElementsAsNodesAndDelimiters` but
+// ignoring delimiters
+std::vector<syntax::Node *> syntax::List::getElementsAsNodes() {
+  if (!firstChild())
+    return {};
+
+  auto children = std::vector<syntax::Node *>();
+  syntax::Node *elementWithoutDelimiter = nullptr;
+  for (auto *C = firstChild(); C; C = C->nextSibling()) {
+    switch (C->role()) {
+    case syntax::NodeRole::List_element: {
+      if (elementWithoutDelimiter) {
+        children.push_back(elementWithoutDelimiter);
+      }
+      elementWithoutDelimiter = C;
+      break;
+    }
+    case syntax::NodeRole::List_delimiter: {
+      children.push_back(elementWithoutDelimiter);
+      elementWithoutDelimiter = nullptr;
+      break;
+    }
+    default:
+      llvm_unreachable("A list has only elements or delimiters.");
+    }
+  }
+
+  switch (getTerminationKind()) {
+  case syntax::List::TerminationKind::Separated: {
+    children.push_back(elementWithoutDelimiter);
+    break;
+  }
+  case syntax::List::TerminationKind::Terminated:
+  case syntax::List::TerminationKind::MaybeTerminated: {
+    if (elementWithoutDelimiter) {
+      children.push_back(elementWithoutDelimiter);
+    }
+    break;
+  }
+  }
+
+  return children;
+}
+
+// The methods below can't be implemented without information about the derived
+// list. These methods will be implemented by switching on the derived list's
+// `NodeKind`
+
+clang::tok::TokenKind syntax::List::getDelimiterTokenKind() {
+  llvm_unreachable("A list can have only elements and delimiters as children.");
+}
+
+syntax::List::TerminationKind syntax::List::getTerminationKind() {
+  llvm_unreachable("A list can have only elements and delimiters as children.");
+}
+
+bool syntax::List::canBeEmpty() {
+  llvm_unreachable("A list can have only elements and delimiters as children.");
+}