diff --git a/CMakeLists.txt b/CMakeLists.txt
index 578105e..3fad734 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,6 +15,7 @@ find_package(builtin_interfaces REQUIRED)
 find_package(action_msgs REQUIRED)
 find_package(geographic_msgs REQUIRED)
 find_package(nav_msgs REQUIRED)
+find_package(ros2_medkit_msgs REQUIRED)
 
 set(dependencies
   std_msgs
@@ -24,6 +25,7 @@ set(dependencies
   nav_msgs
   geographic_msgs
   action_msgs
+  ros2_medkit_msgs
 )
 
 rosidl_generate_interfaces(${PROJECT_NAME}
@@ -32,6 +34,7 @@ rosidl_generate_interfaces(${PROJECT_NAME}
   "msg/CortexFeedback.msg"
   "msg/CortexStatus.msg"
   "msg/FlowCommand.msg"
+  "msg/HealthSummary.msg"
   "msg/HttpRequest.msg"
   "msg/HttpResponse.msg"
   "msg/KeyValue.msg"
@@ -41,6 +44,7 @@ rosidl_generate_interfaces(${PROJECT_NAME}
   "msg/Option.msg"
   "msg/ReferenceTarget.msg"
   "msg/RouteNavGoal.msg"
+  "msg/SubsystemHealth.msg"
   "msg/VehicleCommand.msg"
   "msg/VehicleFeedback.msg"
 
diff --git a/msg/HealthSummary.msg b/msg/HealthSummary.msg
new file mode 100644
index 0000000..120757d
--- /dev/null
+++ b/msg/HealthSummary.msg
@@ -0,0 +1,26 @@
+# Aggregated robot health summary, published periodically by the health
+# aggregator (polymath_health) from the ros2_medkit fault manager's active
+# faults. Downstream consumers treat this as the single source of truth
+
+builtin_interfaces/Time timestamp
+
+# False when the fault source (fault manager) could not be reached; in that case
+# the subsystems/fault arrays are empty.
+bool fault_source_available
+
+# Templated, human-readable one-line summary of the overall health.
+string summary
+
+# Severity of the worst active fault (ros2_medkit_msgs/msg/Fault SEVERITY_* values).
+# Defaults to SEVERITY_INFO when there are no active faults or the fault source is
+# unavailable; use fault_source_available to disambiguate.
+uint8 highest_severity
+
+# fault_code of the worst active fault; empty when there are no active faults.
+string highest_severity_alert
+
+# Number of active faults represented in this summary.
+uint32 active_alert_count
+
+# Per-subsystem rollups, worst-first then alphabetical.
+SubsystemHealth[] subsystems
diff --git a/msg/SubsystemHealth.msg b/msg/SubsystemHealth.msg
new file mode 100644
index 0000000..24ae8f7
--- /dev/null
+++ b/msg/SubsystemHealth.msg
@@ -0,0 +1,12 @@
+# Health rollup for a single subsystem, derived from its active faults.
+# The subsystem name is the lower-cased prefix of a fault_code (text before the
+# first underscore); faults without a prefix are grouped under "uncategorized".
+
+# Subsystem name (e.g. "localization", "compute", "uncategorized").
+string name
+
+# Severity of the worst active fault (ros2_medkit_msgs/msg/Fault SEVERITY_* values).
+uint8 severity
+
+# Individual active faults (verbatim from the fault manager), worst-first then by fault_code.
+ros2_medkit_msgs/Fault[] faults
diff --git a/package.xml b/package.xml
index 437badb..3a76d82 100644
--- a/package.xml
+++ b/package.xml
@@ -2,7 +2,7 @@
 <?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
 <package format="3">
   <name>polymath_msgs</name>
-  <version>0.18.0</version>
+  <version>0.19.0</version>
   <description>Interface definitions for customer applications to communicate with Polymath Autonomy Software</description>
   <maintainer email="dhruv@polymathrobotics.com">Dhruv Tyagi</maintainer>
   <license>Apache-2.0</license>
@@ -16,6 +16,7 @@
   <depend>geometry_msgs</depend>
   <depend>sensor_msgs</depend>
   <depend>action_msgs</depend>
+  <depend>ros2_medkit_msgs</depend>
 
   <build_depend>rosidl_default_generators</build_depend>
   <exec_depend>rosidl_default_runtime</exec_depend>