diff --git a/xl2times/__main__.py b/xl2times/__main__.py
index 1153f66..b342bf7 100644
--- a/xl2times/__main__.py
+++ b/xl2times/__main__.py
@@ -95,6 +95,7 @@ def convert_xl_to_times(
         transforms.convert_aliases,
         transforms.rename_cgs,
         transforms.fix_topology,
+        transforms.final_cleanup,
         transforms.convert_to_string,
         lambda config, tables: dump_tables(
             tables, os.path.join(output_dir, "merged_tables.txt")
@@ -382,6 +383,12 @@ def main():
         nargs="*",
         help="Either an input directory, or a list of input xlsx files to process",
     )
+    args_parser.add_argument(
+        "--regions",
+        type=str,
+        default="",
+        help="Comma-separated list of regions to include in the model",
+    )
     args_parser.add_argument(
         "--output_dir", type=str, default="output", help="Output directory"
     )
@@ -410,6 +417,7 @@ def main():
         "times-info.json",
         "veda-tags.json",
         "veda-attr-defaults.json",
+        args.regions,
     )
 
     if not isinstance(args.input, list) or len(args.input) < 1:
diff --git a/xl2times/datatypes.py b/xl2times/datatypes.py
index db2238b..483cde3 100644
--- a/xl2times/datatypes.py
+++ b/xl2times/datatypes.py
@@ -156,6 +156,8 @@ class Config:
     veda_attr_defaults: Dict[str, Dict[str, list]]
     # Known columns for each tag
     known_columns: Dict[Tag, Set[str]]
+    # Names of regions to include in the model; if empty, all regions are included.
+    filter_regions: Set[str]
 
     def __init__(
         self,
@@ -163,6 +165,7 @@ def __init__(
         times_info_file: str,
         veda_tags_file: str,
         veda_attr_defaults_file: str,
+        regions: str,
     ):
         self.times_xl_maps = Config._read_mappings(mapping_file)
         (
@@ -184,6 +187,7 @@ def __init__(
         for m in param_mappings:
             name_to_map[m.times_name] = m
         self.times_xl_maps = list(name_to_map.values())
+        self.filter_regions = Config._read_regions_filter(regions)
 
     @staticmethod
     def _process_times_info(
@@ -416,3 +420,10 @@ def _read_veda_attr_defaults(
                     veda_attr_defaults["tslvl"][tslvl].append(attr)
 
         return veda_attr_defaults, attr_aliases
+
+    @staticmethod
+    def _read_regions_filter(regions_list: str) -> Set[str]:
+        if regions_list == "":
+            return set()
+        else:
+            return set(regions_list.strip(" ").upper().split(sep=","))
diff --git a/xl2times/transforms.py b/xl2times/transforms.py
index 90fec31..7b56974 100644
--- a/xl2times/transforms.py
+++ b/xl2times/transforms.py
@@ -2160,6 +2160,24 @@ def apply_more_fixups(
     return tables
 
 
+def final_cleanup(
+    config: datatypes.Config, tables: Dict[str, DataFrame]
+) -> Dict[str, DataFrame]:
+    """Apply final clean up. E.g. discard not relevant data"""
+
+    # Apply regions filter
+    # TODO: Apply regions filtering earlier (incl. populating default regions)
+    # TODO: Warn if invalid filter entries?
+    # TODO: Do not filter if no valid filter entries?
+    if config.filter_regions:
+        for k, v in tables.items():
+            if "region" in v.columns:
+                df = v[v["region"].isin(config.filter_regions)]
+                tables[k] = df
+
+    return tables
+
+
 def expand_rows_parallel(
     config: datatypes.Config,
     tables: List[datatypes.EmbeddedXlTable],