diff --git a/common/insert_layer.py b/common/insert_layer.py
new file mode 100755
index 0000000..af4623e
--- /dev/null
+++ b/common/insert_layer.py
@@ -0,0 +1,135 @@
+#!/usr/bin/env python3
+#
+# insert_layer.py:  For the given install path, library name, and cellname,
+# find the Magic layout of the cell, and add the specified layer geometry
+# as given by a layer name and a string with four coordinate values.
+# The layer is added to the layout in both the mag/ (full) and maglef/
+# (abstract) directories.  Option "-maglef" or "-mag" will restrict the
+# use to only the view indicated by the option.
+# 
+# e.g.:
+#
+# insert_layer.py /path/to/sky130A \
+#	sky130_fd_io sky130_fd_sc_hd__a21bo_1 pwell "29 17 69 157" -mag
+
+import os
+import re
+import sys
+
+def addlayer(filename, layer, geometry):
+    with open(filename, 'r') as ifile:
+        magtext = ifile.read().splitlines() 
+
+    layerrex = re.compile('<< ' + layer + ' >>')
+    sectionrex = re.compile('<< ')
+    labelsrex = re.compile('<< labels >>')
+    endrex = re.compile('<< end >>')
+
+    in_layer = False
+    done = False
+
+    with open(filename, 'w') as ofile:
+        for line in magtext:
+            if not done and not in_layer:
+                # Handle case in which layer did not already exist in file
+                lmatch = labelsrex.match(line)
+                ematch = endrex.match(line)
+                if lmatch or ematch:
+                    print('<< ' + layer + '>>', file=ofile)
+                    print('rect ' + geometry, file=ofile)
+                    done = True
+            
+            lmatch = layerrex.match(line)
+            if lmatch:
+                in_layer = True
+            elif in_layer:
+                smatch = sectionrex.match(line)
+                if smatch:
+                    print('rect ' + geometry, file=ofile)
+                    in_layer = False
+                    done = True
+
+            print(line, file=ofile)
+
+def usage():
+    print("insert_layer.py <path_to_pdk> <libname> <cellname> <layer> <geometry> [option]")
+    print("  options:")
+    print("   -mag      do only for the view in the mag/ directory")
+    print("   -maglef   do only for the view in the maglef/ directory")
+    return 0
+
+if __name__ == '__main__':
+
+    options = []
+    arguments = []
+    for item in sys.argv[1:]:
+        if item.find('-', 0) == 0:
+            options.append(item)
+        else:
+            arguments.append(item)
+
+    if len(arguments) < 5:
+        print("Not enough options given to insert_layer.py.")
+        usage()
+        sys.exit(0)
+
+    source = arguments[0]
+    libname = arguments[1]
+    cellname = arguments[2]
+    layer = arguments[3]
+    geometry = arguments[4]
+
+    # Diagnostic
+    print('insert_layer.py:')
+    print('   source   = ' + source)
+    print('   library  = ' + libname)
+    print('   cell     = ' + cellname)
+    print('   layer    = ' + layer)
+    print('   geometry = ' + geometry)
+
+    fail = 0
+
+    efformat = True if '-ef_format' in options else False
+
+    domag = True
+    domaglef = True
+    if '-mag' in options and '-maglef' not in options:
+        domaglef = False
+    if '-maglef' in options and '-mag' not in options:
+        domag = False
+
+    if domag:
+        if efformat:
+            filename = source + '/libs.ref/mag/' + libname + '/' + cellname + '.mag'
+        else:
+            filename = source + '/libs.ref/' + libname + '/mag/' + cellname + '.mag'
+
+        if os.path.isfile(filename):
+            addlayer(filename, layer, geometry)
+        else:
+            fail += 1
+    else:
+        fail += 1
+
+    if domaglef:
+        if efformat:
+            filename = source + '/libs.ref/maglef/' + libname + '/' + cellname + '.mag'
+        else:
+            filename = source + '/libs.ref/' + libname + '/maglef/' + cellname + '.mag'
+
+        if os.path.isfile(filename):
+            addlayer(filename, layer, geometry)
+        else:
+            fail += 1
+    else:
+        fail += 1
+
+    if fail == 2:
+        print('Error:  No layout file in either mag/ or maglef/', file=sys.stderr)
+        if efformat:
+            print('(' + source + '/libs.ref/mag[lef]/' + libname +
+		    '/' + cellname + '.mag)', file=sys.stderr)
+        else:
+            print('(' + source + '/libs.ref/' + libname + '/mag[lef]/'
+		    + cellname + '.mag)', file=sys.stderr)
+