diff --git a/CHANGES.rst b/CHANGES.rst
index 0f66ab5c..cb3fa05e 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -16,6 +16,7 @@
 
 - Updated product table names. [#382]
 
+- Added schema for Source Catalog and Segmentation Map. [#374]
 
 0.19.0 (2024-02-09)
 -------------------
diff --git a/src/rad/resources/manifests/datamodels-1.0.yaml b/src/rad/resources/manifests/datamodels-1.0.yaml
index e2c0a5b7..0e2aad7e 100644
--- a/src/rad/resources/manifests/datamodels-1.0.yaml
+++ b/src/rad/resources/manifests/datamodels-1.0.yaml
@@ -263,6 +263,16 @@ tags:
   title: Calibration reference file names.
   description: |-
     Calibration reference file names.
+- tag_uri: asdf://stsci.edu/datamodels/roman/tags/source_catalog-1.0.0
+  schema_uri: asdf://stsci.edu/datamodels/roman/schemas/source_catalog-1.0.0
+  title: Source catalog
+  description: |-
+    Photometry and astrometry computed by the Source Catalog Step
+- tag_uri: asdf://stsci.edu/datamodels/roman/tags/segmentation_map-1.0.0
+  schema_uri: asdf://stsci.edu/datamodels/roman/schemas/segmentation_map-1.0.0
+  title: Segmentation map
+  description: |-
+    Segmentation map computed by the Source Catalog Step
 # Tagged Scalars
 - tag_uri: asdf://stsci.edu/datamodels/roman/tags/calibration_software_version-1.0.0
   schema_uri: asdf://stsci.edu/datamodels/roman/schemas/tagged_scalars/calibration_software_version-1.0.0
diff --git a/src/rad/resources/schemas/segmentation_map-1.0.0.yaml b/src/rad/resources/schemas/segmentation_map-1.0.0.yaml
new file mode 100644
index 00000000..dedc733f
--- /dev/null
+++ b/src/rad/resources/schemas/segmentation_map-1.0.0.yaml
@@ -0,0 +1,38 @@
+%YAML 1.1
+---
+$schema: asdf://stsci.edu/datamodels/roman/schemas/rad_schema-1.0.0
+id: asdf://stsci.edu/datamodels/roman/schemas/segmentation_map-1.0.0
+
+title: Segmentation map generated by the Source Catalog Step.
+
+datamodel_name: SegmentationMapModel
+
+archive_meta: None
+type: object
+properties:
+  meta:
+    allOf:
+      - type: object
+        properties:
+          basic:
+            tag: asdf://stsci.edu/datamodels/roman/tags/mosaic_basic-1.0.0
+          coordinates:
+            tag: asdf://stsci.edu/datamodels/roman/tags/coordinates-1.0.0
+          program:
+            tag: asdf://stsci.edu/datamodels/roman/tags/program-1.0.0
+          wcsinfo:
+            tag: asdf://stsci.edu/datamodels/roman/tags/mosaic_wcsinfo-1.0.0
+        required: [basic, coordinates, program, wcsinfo]
+  data:
+    title: Segmentation map
+    description: |
+       Segmentation map of an image model, zeros correspond to background.
+    tag: tag:stsci.edu:asdf/core/ndarray-1.*
+    ndim: 2
+    datatype: uint32
+    exact_datatype: true
+
+required: [meta, data]
+flowStyle: block
+propertyOrder: [meta, data]
+...
diff --git a/src/rad/resources/schemas/source_catalog-1.0.0.yaml b/src/rad/resources/schemas/source_catalog-1.0.0.yaml
new file mode 100644
index 00000000..0955436b
--- /dev/null
+++ b/src/rad/resources/schemas/source_catalog-1.0.0.yaml
@@ -0,0 +1,37 @@
+%YAML 1.1
+---
+$schema: asdf://stsci.edu/datamodels/roman/schemas/rad_schema-1.0.0
+id: asdf://stsci.edu/datamodels/roman/schemas/source_catalog-1.0.0
+
+title: Source catalog generated by the Source Catalog Step.
+
+datamodel_name: SourceCatalogModel
+
+archive_meta: None
+type: object
+properties:
+  meta:
+    allOf:
+      - type: object
+        properties:
+          basic:
+            tag: asdf://stsci.edu/datamodels/roman/tags/mosaic_basic-1.0.0
+          coordinates:
+            tag: asdf://stsci.edu/datamodels/roman/tags/coordinates-1.0.0
+          photometry:
+            tag: asdf://stsci.edu/datamodels/roman/tags/photometry-1.0.0
+          program:
+            tag: asdf://stsci.edu/datamodels/roman/tags/program-1.0.0
+          wcsinfo:
+            tag: asdf://stsci.edu/datamodels/roman/tags/mosaic_wcsinfo-1.0.0
+        required: [basic, coordinates, photometry, program, wcsinfo]
+  source_catalog:
+    title: Source Catalog
+    description: |
+       Photometry and astrometry computed in the Source Catalog Step.
+    tag: tag:astropy.org:astropy/table/table-1.*
+
+required: [meta, source_catalog]
+flowStyle: block
+propertyOrder: [meta, source_catalog]
+...