diff --git a/rtc_base/trace_event.h b/rtc_base/trace_event.h
index 32ad031385..6689bc0c37 100644
--- a/rtc_base/trace_event.h
+++ b/rtc_base/trace_event.h
@@ -430,6 +430,100 @@
                                    name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
                                    arg1_val, arg2_name, arg2_val)
 
+// Records a single FLOW_BEGIN event called "name" immediately, with 0, 1 or 2
+// associated arguments. If the category is not enabled, then this
+// does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - `id` is used to match the FLOW_BEGIN event with the FLOW_END event. FLOW
+//   events are considered to match if their category, name and id values all
+//   match. `id` must either be a pointer or an integer value up to 64 bits. If
+//   it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+// FLOW events are different from ASYNC events in how they are drawn by the
+// tracing UI. A FLOW defines asynchronous data flow, such as posting a task
+// (FLOW_BEGIN) and later executing that task (FLOW_END). Expect FLOWs to be
+// drawn as lines or arrows from FLOW_BEGIN scopes to FLOW_END scopes. Similar
+// to ASYNC, a FLOW can consist of multiple phases. The first phase is defined
+// by the FLOW_BEGIN calls. Additional phases can be defined using the FLOW_STEP
+// macros. When the operation completes, call FLOW_END. An async operation can
+// span threads and processes, but all events in that operation must use the
+// same `name` and `id`. Each event can have its own args.
+#define TRACE_EVENT_FLOW_BEGIN0(category, name, id)                        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category, \
+                                   name, id, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category,     \
+                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
+                                   arg1_val)
+#define TRACE_EVENT_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val,       \
+                                arg2_name, arg2_val)                           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category,     \
+                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
+                                   arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_FLOW_BEGIN0(category, name, id)                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category, \
+                                   name, id, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val)  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category,     \
+                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
+                                   arg1_val)
+#define TRACE_EVENT_COPY_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val,  \
+                                     arg2_name, arg2_val)                      \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, category,     \
+                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
+                                   arg1_val, arg2_name, arg2_val)
+
+// Records a single FLOW_STEP event for `step` immediately. If the category
+// is not enabled, then this does nothing. The `name` and `id` must match the
+// FLOW_BEGIN event above. The `step` param identifies this step within the
+// async event. This should be called at the beginning of the next phase of an
+// asynchronous operation.
+#define TRACE_EVENT_FLOW_STEP0(category, name, id, step)                    \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, category,   \
+                                   name, id, TRACE_EVENT_FLAG_NONE, "step", \
+                                   step)
+#define TRACE_EVENT_FLOW_STEP1(category, name, id, step, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, category,     \
+                                   name, id, TRACE_EVENT_FLAG_NONE, "step",   \
+                                   step, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_FLOW_STEP0(category, name, id, step)               \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, category,   \
+                                   name, id, TRACE_EVENT_FLAG_COPY, "step", \
+                                   step)
+#define TRACE_EVENT_COPY_FLOW_STEP1(category, name, id, step, arg1_name,    \
+                                    arg1_val)                               \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, category,   \
+                                   name, id, TRACE_EVENT_FLAG_COPY, "step", \
+                                   step, arg1_name, arg1_val)
+
+// Records a single FLOW_END event for "name" immediately. If the category
+// is not enabled, then this does nothing.
+#define TRACE_EVENT_FLOW_END0(category, name, id)                              \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_FLOW_END1(category, name, id, arg1_name, arg1_val)         \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_NONE, arg1_name,       \
+                                   arg1_val)
+#define TRACE_EVENT_FLOW_END2(category, name, id, arg1_name, arg1_val,         \
+                              arg2_name, arg2_val)                             \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_NONE, arg1_name,       \
+                                   arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_FLOW_END0(category, name, id)                         \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_FLOW_END1(category, name, id, arg1_name, arg1_val)    \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_COPY, arg1_name,       \
+                                   arg1_val)
+#define TRACE_EVENT_COPY_FLOW_END2(category, name, id, arg1_name, arg1_val,    \
+                                   arg2_name, arg2_val)                        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category, name, \
+                                   id, TRACE_EVENT_FLAG_COPY, arg1_name,       \
+                                   arg1_val, arg2_name, arg2_val)
+
 ////////////////////////////////////////////////////////////////////////////////
 // Implementation specific tracing API definitions.
 
@@ -536,6 +630,9 @@
 #define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S')
 #define TRACE_EVENT_PHASE_ASYNC_STEP ('T')
 #define TRACE_EVENT_PHASE_ASYNC_END ('F')
+#define TRACE_EVENT_PHASE_FLOW_BEGIN ('s')
+#define TRACE_EVENT_PHASE_FLOW_STEP ('t')
+#define TRACE_EVENT_PHASE_FLOW_END ('f')
 #define TRACE_EVENT_PHASE_METADATA ('M')
 #define TRACE_EVENT_PHASE_COUNTER ('C')
 
@@ -912,6 +1009,40 @@ class TraceEndOnScopeClose {
                                     arg2_name, arg2_val)                     \
   RTC_NOOP()
 
+#define TRACE_EVENT_FLOW_BEGIN0(category, name, id) RTC_NOOP()
+#define TRACE_EVENT_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val) \
+  RTC_NOOP()
+#define TRACE_EVENT_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val, \
+                                arg2_name, arg2_val)                     \
+  RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_BEGIN0(category, name, id) RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val) \
+  RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val, \
+                                     arg2_name, arg2_val)                     \
+  RTC_NOOP()
+
+#define TRACE_EVENT_FLOW_STEP0(category, name, id, step) RTC_NOOP()
+#define TRACE_EVENT_FLOW_STEP1(category, name, id, step, arg1_name, arg1_val) \
+  RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_STEP0(category, name, id, step) RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_STEP1(category, name, id, step, arg1_name, \
+                                    arg1_val)                            \
+  RTC_NOOP()
+
+#define TRACE_EVENT_FLOW_END0(category, name, id) RTC_NOOP()
+#define TRACE_EVENT_FLOW_END1(category, name, id, arg1_name, arg1_val) \
+  RTC_NOOP()
+#define TRACE_EVENT_FLOW_END2(category, name, id, arg1_name, arg1_val, \
+                              arg2_name, arg2_val)                     \
+  RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_END0(category, name, id) RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_END1(category, name, id, arg1_name, arg1_val) \
+  RTC_NOOP()
+#define TRACE_EVENT_COPY_FLOW_END2(category, name, id, arg1_name, arg1_val, \
+                                   arg2_name, arg2_val)                     \
+  RTC_NOOP()
+
 #define TRACE_EVENT_API_GET_CATEGORY_ENABLED ""
 
 #define TRACE_EVENT_API_ADD_TRACE_EVENT RTC_NOOP()