diff --git a/bin/ecbundle b/bin/ecbundle
index 642e9c2..32558ad 100755
--- a/bin/ecbundle
+++ b/bin/ecbundle
@@ -37,6 +37,9 @@ elif [[ "create" == "$1"* ]]; then
 elif [[ "populate" == "$1"* ]]; then
   shift
   ${SCRIPT_DIR}/ecbundle-populate "$@"
+elif [[ "merge" == "$1"* ]]; then
+  shift
+  ${SCRIPT_DIR}/ecbundle-merge "$@"
 else
   echo "ERROR: Expected 'build' or 'create' or 'populate' as first argument"
   usage
diff --git a/bin/ecbundle-merge b/bin/ecbundle-merge
new file mode 100755
index 0000000..6a2572a
--- /dev/null
+++ b/bin/ecbundle-merge
@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+
+# (C) Copyright 2020- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation nor
+# does it submit to any jurisdiction.
+
+"""
+Script to merge and update bundle files
+"""
+
+import os
+import sys
+from argparse import SUPPRESS, ArgumentParser, RawTextHelpFormatter
+
+sys.path.insert(0, os.path.realpath(os.path.dirname(os.path.realpath(__file__))+'/..'))
+from ecbundle import BundleMerger
+from ecbundle.logging import DEBUG, colors, error, logger, success
+
+
+def main():
+
+    # Parse arguments
+    parser = ArgumentParser(description=__doc__,
+                            formatter_class=RawTextHelpFormatter)
+
+    # --------------------------------------------------------------------------
+    # Parse common subcommands
+    # --------------------------------------------------------------------------
+    parser.add_argument('--no-colour', '--no-color',
+                        help='Disable color output',
+                        action='store_true')
+
+    parser.add_argument('--verbose', '-v',
+                        help='Verbose output',
+                        action='store_true')
+
+    parser.add_argument('--bundle',
+                        help='Configuration of bundle', default="bundle.yml")
+
+    parser.add_argument('--bundle-update',
+                        help='Configuration of bundle update', default="bundle-update.yml")
+
+    parser.add_argument('-o',
+                        help='output file', default="merged-bundle.yml")
+
+    # --------------------------------------------------------------------------
+
+    # Close parser and populate variable args
+    args = parser.parse_args()
+
+    # Explicitly disable coloured logs
+    if args.no_colour:
+        colors.disable()
+
+    # Log everything, including commands executed
+    if args.verbose:
+        logger.setLevel(DEBUG)
+
+
+    errcode = 0
+
+    if BundleMerger(**vars(args)).merge() != 0:
+        errcode = 1 # error
+
+    if errcode == 1:
+        error("\n!!! Errors occured !!!")
+
+    return errcode
+
+if __name__ == '__main__':
+    sys.exit(main())
diff --git a/ecbundle/__init__.py b/ecbundle/__init__.py
index 1e2dde7..998c03f 100644
--- a/ecbundle/__init__.py
+++ b/ecbundle/__init__.py
@@ -12,6 +12,7 @@
 from ecbundle.download import *  # noqa
 from ecbundle.git import *  # noqa
 from ecbundle.logging import *  # noqa
+from ecbundle.merge import *  # noqa
 from ecbundle.option import *  # noqa
 from ecbundle.populate import *  # noqa
 from ecbundle.project import *  # noqa
diff --git a/ecbundle/merge.py b/ecbundle/merge.py
new file mode 100644
index 0000000..73c6f65
--- /dev/null
+++ b/ecbundle/merge.py
@@ -0,0 +1,115 @@
+# (C) Copyright 2020- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation nor
+# does it submit to any jurisdiction.
+
+import copy
+import os
+
+from .bundle import Bundle
+from .logging import error, header, success
+from .util import fullpath
+
+__all__ = ["BundleMerger"]
+
+
+class BundleMerger(object):
+    def __init__(self, **kwargs):
+        self.config = kwargs
+
+    def get(self, key, default=None):
+        return self.config[key] if self.config[key] is not None else default
+
+    def deep_merge(self, original, updates):
+        """Recursively merge `updates` into `original`.
+
+        Rules:
+        - Dictionaries and  are merged recursively.
+        - lists and scalar values are replaced entirely.
+        - Keys missing from `updates` remain unchanged.
+        """
+        if isinstance(original, dict) and isinstance(updates, dict):
+            merged = copy.deepcopy(original)
+            for key, value in updates.items():
+                if key in merged:
+                    if isinstance(merged[key], dict) and isinstance(value, dict):
+                        merged[key] = self.deep_merge(merged[key], value)
+                    else:
+                        merged[key] = copy.deepcopy(value)
+
+                else:
+                    merged[key] = copy.deepcopy(value)
+
+        else:
+            return copy.deepcopy(updates)
+
+        return merged
+
+    def bundle(self, update=False):
+        arg = "bundle"
+        if update:
+            arg += "_update"
+        bundle_path = fullpath(self.get(arg, None))
+        if bundle_path:
+            if os.path.isfile(bundle_path):
+                return Bundle(bundle_path, env=True)
+            if not os.path.isdir(bundle_path):
+                error(f"ERROR: --{arg} argument is not a valid bundle file path")
+                return None
+
+        return None
+
+    def merge(self):
+        bundle = self.bundle()
+        bundle_update = self.bundle(update=True)
+        if not (bundle and bundle_update):
+            return 1
+
+        success("\nMerging bundle  ")
+        header(f"    {bundle_update.file()} into {bundle.file()}")
+
+        # merging projects
+        project_dict = {
+            item.config["name"]: {k: v for k, v in item.config.items() if k != "name"}
+            for item in bundle.projects()
+        }
+
+        updated_project_dict = {
+            item.config["name"]: {k: v for k, v in item.config.items() if k != "name"}
+            for item in bundle_update.projects()
+        }
+
+        updated_dict = self.deep_merge(project_dict, updated_project_dict)
+
+        bundle.config["projects"] = [
+            {key: value} for key, value in updated_dict.items()
+        ]
+
+        # merging options
+        option_dict = {
+            item.config["name"]: {k: v for k, v in item.config.items() if k != "name"}
+            for item in bundle.options()
+        }
+
+        updated_option_dict = {
+            item.config["name"]: {k: v for k, v in item.config.items() if k != "name"}
+            for item in bundle_update.options()
+        }
+
+        updated_dict = self.deep_merge(option_dict, updated_option_dict)
+
+        bundle.config["options"] = [{key: value} for key, value in updated_dict.items()]
+
+        # merge remaining keys
+
+        for key in bundle_update.config.keys():
+            if key not in ["projects", "options"]:
+                bundle.config[key] = bundle_update.get(key)
+
+        with open(self.get("o", None), "w", encoding="utf-8") as f:
+            f.write(bundle.yaml())
+
+        return 0
diff --git a/ecbundle/project.py b/ecbundle/project.py
index dfe8fe5..a55b28e 100644
--- a/ecbundle/project.py
+++ b/ecbundle/project.py
@@ -74,6 +74,9 @@ def require(self):
         else:
             return None
 
+    def get_dict(self):
+        return self.config
+
     def optional(self):
         return self.get("optional", False)