diff --git a/simplecli/simplecli.py b/simplecli/simplecli.py
index 56d9dc6..3779aa0 100644
--- a/simplecli/simplecli.py
+++ b/simplecli/simplecli.py
@@ -22,6 +22,7 @@
     get_args,
     get_origin,
 )
+from types import GenericAlias
 
 try:
     from types import UnionType
@@ -50,6 +51,7 @@ class UnsupportedType(TypeError):
 ValueType = Union[type[DefaultIfBool], type[Empty], bool, float, int, str]
 ArgDict = dict[str, ValueType]
 ArgList = list[str]
+valid_origins = (Union, UnionType, list, set)
 
 
 class Param(inspect.Parameter):
@@ -86,16 +88,25 @@ def __init__(self, *argv: Any, **kwargs: Any) -> None:
         # Overrides required as these values are generally unused
         if not self.description:
             self.parse_or_prepend(param_line)
-        annotation = kwargs["annotation"]
-        if annotation not in get_args(ValueType):
-            if get_origin(annotation) not in (Union, UnionType):
-                if annotation is not Empty:
-                    pretty_annotation = (
-                        annotation
-                        if type(annotation) is type
-                        else annotation.__class__.__name__
-                    )
-                    raise UnsupportedType(kwargs["name"], pretty_annotation)
+        self.validate_annotation(kwargs["name"], kwargs["annotation"])
+
+    def validate_annotation(self, name: str, annotation: object) -> None:
+        if annotation in get_args(ValueType):
+            return
+        if get_origin(annotation) in valid_origins:
+            return
+        if annotation is Empty:
+            return
+
+        pretty_annotation = (
+            annotation
+            if (
+                type(annotation) is type
+                or isinstance(annotation, GenericAlias)
+            )
+            else annotation.__class__.__name__
+        )
+        raise UnsupportedType(name, pretty_annotation)
 
     def __eq__(self, other: object) -> bool:
         if not isinstance(other, Param):
@@ -154,7 +165,7 @@ def help_name(self) -> str:
 
     @property
     def help_type(self) -> str:
-        if get_origin(self.annotation) in (Union, UnionType):
+        if get_origin(self.annotation) in valid_origins:
             typelist = ", ".join([a.__name__ for a in self.datatypes])
             return f"[{typelist}]"
         return self.annotation.__name__
@@ -204,6 +215,9 @@ def datatypes(self) -> list[type]:
         return [self.annotation]
 
     def validate(self, value: ValueType) -> bool:
+        # Recurse for list handling
+        if isinstance(value, list):
+            return all(self.validate(v) for v in value)
         passed = False
         for expected_type in self.datatypes:
             if expected_type is type(None):
@@ -223,7 +237,8 @@ def set_value(self, value: ValueType) -> None:
             )
         # Handle datatypes
         args = get_args(self.annotation)
-        if args:
+        origin = get_origin(self.annotation)
+        if origin in (Union, UnionType):
             for type_arg in args:
                 with (
                     contextlib.suppress(TypeError),
@@ -239,6 +254,19 @@ def set_value(self, value: ValueType) -> None:
             result = value
         self._value = self.annotation(result)
 
+    def set_value_as_seq(self, values: ArgList) -> None:
+        args = get_args(self.annotation)
+        origin = get_origin(self.annotation)
+        self._value = []
+        temp_value = []
+        for value in values:
+            if self.validate(value) is False:
+                raise ValueError(
+                    f"'{self.help_name}' must be of type {self.help_type}"
+                )
+            temp_value.append(args[0](value))
+        self._value = origin(temp_value)
+
 
 def tokenize_string(string: str) -> Generator[TokenInfo, None, None]:
     return generate_tokens(io.StringIO(string).readline)
@@ -317,21 +345,19 @@ def params_to_kwargs(
     missing_params = []
     try:
         for param in params:
+            kw_value = kw_args.get(param.name)
+            if get_origin(param.annotation) in (list, set):
+                # Consume ALL pos_args if list or set
+                param.set_value_as_seq(pos_args)
+                pos_args.clear()
             # Positional arguments take precedence
-            if pos_args:
+            elif pos_args:
                 param.set_value(pos_args.pop(0))
-            elif param.name in kw_args:
-                if kw_args[param.name] is DefaultIfBool:
-                    # Invert the default value
-                    param.set_value(
-                        True if param.default is Empty else not param.default
-                    )
-                    continue
-                param.set_value(kw_args[param.name])
+            elif kw_value:
+                param.set_value(kw_value)
                 continue
             elif param.required:
                 missing_params.append(param)
-                continue
     except ValueError as e:
         exit(e.args[0])
 
diff --git a/tests/test_param.py b/tests/test_param.py
index f8d64fd..ce5322f 100644
--- a/tests/test_param.py
+++ b/tests/test_param.py
@@ -190,3 +190,25 @@ def test_param_boolean_implied_false():
     assert p1.required is False
     assert p1.optional is False
     assert p1.value is False
+
+
+def test_param_validate_list():
+    p1 = Param(name="testparam1", annotation=list[str])
+    assert p1.validate(["foo", "bar"]) is True
+    assert p1.required is True
+    assert p1.optional is False
+
+
+def test_param_set_value_as_seq_valid():
+    p1 = Param(name="testparam1", annotation=list[str])
+    p1.set_value_as_seq([123, "bar"])
+    assert p1.required is True
+    assert p1.optional is False
+
+
+def test_param_set_value_as_seq_invalid():
+    p1 = Param(name="testparam1", annotation=list[int])
+    with pytest.raises(ValueError, match="int"):
+        p1.set_value_as_seq([123, "bar"])
+    assert p1.required is True
+    assert p1.optional is False
diff --git a/tests/test_wrap.py b/tests/test_wrap.py
index 78c0620..f5bab6a 100644
--- a/tests/test_wrap.py
+++ b/tests/test_wrap.py
@@ -27,11 +27,15 @@ def code1(a: int):
     def code2(a: int):
         pass
 
+    code1_name = code1.__globals__["__name__"]
+    code2_name = code2.__globals__["__name__"]
     with pytest.raises(SystemExit, match="only ONE"):
         code1.__globals__["__name__"] = "__main__"
         code2.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
         simplecli.wrap(code2)
+    code1.__globals__["__name__"] = code1_name
+    code2.__globals__["__name__"] = code2_name
 
 
 def test_wrap_help_simple(monkeypatch):
@@ -40,9 +44,11 @@ def test_wrap_help_simple(monkeypatch):
     def code1(this_var: int):  # stuff and things
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
 
     help_msg = e.value.args[0]
     assert "--this-var" in help_msg
@@ -59,9 +65,11 @@ def code(
     ):
         pass
 
+    code_name = code.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code.__globals__["__name__"] = "__main__"
         simplecli.wrap(code)
+    code.__globals__["__name__"] = code_name
 
     help_msg = e.value.args[0]
     assert "--that-var" in help_msg
@@ -76,9 +84,11 @@ def test_wrap_simple_type_error(monkeypatch):
     def code(a: int):
         pass
 
+    code_name = code.__globals__["__name__"]
     with pytest.raises(SystemExit, match="Too many positional"):
         code.__globals__["__name__"] = "__main__"
         simplecli.wrap(code)
+    code.__globals__["__name__"] = code_name
 
 
 def test_wrap_simple_value_error(monkeypatch):
@@ -87,9 +97,11 @@ def test_wrap_simple_value_error(monkeypatch):
     def code(a: int):
         pass
 
+    code_name = code.__globals__["__name__"]
     with pytest.raises(SystemExit, match="must be of type int"):
         code.__globals__["__name__"] = "__main__"
         simplecli.wrap(code)
+    code.__globals__["__name__"] = code_name
 
 
 def test_wrap_version_absent(monkeypatch):
@@ -98,9 +110,11 @@ def test_wrap_version_absent(monkeypatch):
     def code2(this_var: int):  # stuff and things
         pass
 
+    code2_name = code2.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code2.__globals__["__name__"] = "__main__"
         simplecli.wrap(code2)
+    code2.__globals__["__name__"] = code2_name
 
     help_msg = e.value.args[0]
     assert "Description:" not in help_msg
@@ -115,10 +129,12 @@ def test_wrap_version_exists(monkeypatch):
     def code1(this_var: int):  # stuff and things
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code1.__globals__["__name__"] = "__main__"
         code1.__globals__["__version__"] = "1.2.3"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
 
     help_msg = e.value.args[0]
     assert "super_script version 1.2.3" in help_msg
@@ -135,9 +151,11 @@ def code2(this_var: int):  # stuff and things
         this is a description
         """
 
+    code2_name = code2.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code2.__globals__["__name__"] = "__main__"
         simplecli.wrap(code2)
+    code2.__globals__["__name__"] = code2_name
 
     help_msg = e.value.args[0]
     assert "Description:" in help_msg
@@ -156,9 +174,11 @@ def code(
     ):
         pass
 
+    code_name = code.__globals__["__name__"]
     with pytest.raises(SystemExit) as e:
         code.__globals__["__name__"] = "__main__"
         simplecli.wrap(code)
+    code.__globals__["__name__"] = code_name
 
     help_msg = e.value.args[0]
     assert "--that-var" in help_msg
@@ -174,10 +194,12 @@ def test_wrap_simple_positional(capfd, monkeypatch):
     def code(a: int, b: int, c: typing.Union[int, float]):
         print(a + b + c)
 
+    code_name = code.__globals__["__name__"]
     code.__globals__["__name__"] = "__main__"
     simplecli.wrap(code)
     (out, _) = capfd.readouterr()
     assert out.strip() == "6.5"
+    code.__globals__["__name__"] = code_name
 
 
 def test_wrap_boolean_false(monkeypatch):
@@ -241,9 +263,11 @@ def test_wrap_no_typehint_(monkeypatch):
     def code1(foo):
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit, match="parameters need type hints!"):
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
 
 
 def test_wrap_no_typehint_no_arg(monkeypatch):
@@ -252,9 +276,11 @@ def test_wrap_no_typehint_no_arg(monkeypatch):
     def code1(foo):
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit, match="ERROR: All wrapped function "):
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
 
 
 def test_wrap_no_typehint_kwarg(monkeypatch):
@@ -263,9 +289,11 @@ def test_wrap_no_typehint_kwarg(monkeypatch):
     def code1(foo):
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit, match="function parameters need type"):
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
 
 
 def test_wrap_unsupported_type(monkeypatch):
@@ -274,6 +302,60 @@ def test_wrap_unsupported_type(monkeypatch):
     def code1(foo: [str, int]):
         pass
 
+    code1_name = code1.__globals__["__name__"]
     with pytest.raises(SystemExit, match="UnsupportedType: list"):
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+    code1.__globals__["__name__"] = code1_name
+
+
+def test_wrap_list_of_strings(capfd, monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["fn", "this", "is", "a", "test"])
+
+    def code1(foo: list[str]):
+        print(" | ".join(foo))
+
+    code1_name = code1.__globals__["__name__"]
+    code1.__globals__["__name__"] = "__main__"
+    simplecli.wrap(code1)
+    assert capfd.readouterr().out == "this | is | a | test\n"
+    code1.__globals__["__name__"] = code1_name
+
+
+def test_wrap_list_of_ints(capfd, monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["filename", "8", "6", "7", "53", "09"])
+
+    def code1(foo: list[int]):
+        print(sum(foo))
+
+    code1_name = code1.__globals__["__name__"]
+    code1.__globals__["__name__"] = "__main__"
+    simplecli.wrap(code1)
+    assert capfd.readouterr().out == "83\n"
+    code1.__globals__["__name__"] = code1_name
+
+
+def test_wrap_set_of_ints_different(capfd, monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["filename", "8", "6", "7", "53", "09"])
+
+    def code1(foo: set[int]):
+        print(sum(foo))
+
+    code1_name = code1.__globals__["__name__"]
+    code1.__globals__["__name__"] = "__main__"
+    simplecli.wrap(code1)
+    assert capfd.readouterr().out == "83\n"
+    code1.__globals__["__name__"] = code1_name
+
+
+def test_wrap_set_of_ints_same(capfd, monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["filename", "8", "8", "8", "1", "08"])
+
+    def code1(foo: set[int]):
+        print(sum(foo))
+
+    code1_name = code1.__globals__["__name__"]
+    code1.__globals__["__name__"] = "__main__"
+    simplecli.wrap(code1)
+    assert capfd.readouterr().out == "9\n"
+    code1.__globals__["__name__"] = code1_name