diff --git a/requirements-dev.txt b/requirements-dev.txt
index 38017040a..9785a32e3 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,4 +1,6 @@
 ruff==0.4.2
 pre-commit==3.7.0
+pytest==8.2.0
 Pyinstaller==6.6.0
 mypy==1.10.0
+pytest-mock 3.14.0
\ No newline at end of file
diff --git a/tagstudio/tests/core/test_tags.py b/tagstudio/tests/core/test_tags.py
index f3cd57915..30f781174 100644
--- a/tagstudio/tests/core/test_tags.py
+++ b/tagstudio/tests/core/test_tags.py
@@ -1,7 +1,32 @@
+import sys
+import os
+import pytest
+
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '..')))
+
 from src.core.library import Tag
 
+@pytest.fixture
+def mock_library(mocker):
+    return mocker.Mock()
+
+@pytest.fixture
+def mock_subtag(mocker):
+    return mocker.Mock()
+
+@pytest.fixture
+def test_tag1():
+    return Tag(id=1, name="tag1 Name", shorthand="tag1", aliases=[], subtags_ids=[2], color="")
 
-class TestTags:
+@pytest.fixture
+def test_tag2():
+    return Tag(id=2, name="tag2 Name", shorthand="tag2", aliases=[], subtags_ids=[3], color="")
+
+@pytest.fixture
+def test_tag3():
+    return Tag(id=3, name="tag3 Name", shorthand="tag3", aliases=[], subtags_ids=[], color="")
+
+class TestTags():
     def test_construction(self):
         tag = Tag(
             id=1,
@@ -12,7 +37,125 @@ def test_construction(self):
             color="",
         )
         assert tag
+        assert tag.id == 1
+        assert tag.name == "Tag Name"
+        assert tag.shorthand == "TN"
+        assert tag.aliases == ["First A", "Second A"]
+        assert tag.subtag_ids == [2, 3, 4]
+        assert tag.color == ""
 
     def test_empty_construction(self):
         tag = Tag(id=1, name="", shorthand="", aliases=[], subtags_ids=[], color="")
-        assert tag
+        assert tag.id == 1
+        assert tag.name == ""
+        assert tag.shorthand == ""
+        assert tag.aliases == []
+        assert tag.subtag_ids == []
+        assert tag.color == ""
+
+    def test_add_subtag(self, test_tag1):
+        test_tag1.subtag_ids = []
+        assert test_tag1.subtag_ids == []
+        assert len(test_tag1.subtag_ids) == 0
+
+        test_tag1.add_subtag(2)
+        test_tag1.add_subtag(3)
+        assert test_tag1.subtag_ids == [2,3]
+        assert len(test_tag1.subtag_ids) == 2
+
+        #No Duplicates added
+        test_tag1.add_subtag(2)
+        assert len(test_tag1.subtag_ids) == 2
+        assert test_tag1.subtag_ids == [2,3]
+
+    def test_remove_subtag(self, test_tag1):
+        test_tag1.subtag_ids = [1,2,3,4,5]
+        assert len(test_tag1.subtag_ids) == 5
+
+        test_tag1.remove_subtag(3)
+        assert len(test_tag1.subtag_ids) == 4
+        assert test_tag1.subtag_ids == [1,2,4,5]
+
+        test_tag1.remove_subtag(2)
+        assert len(test_tag1.subtag_ids) == 3
+        assert test_tag1.subtag_ids == [1,4,5]
+
+    def test_remove_subtag_not_in_subtag_ids(self, test_tag1):
+        test_tag1.remove_subtag(1)
+        assert test_tag1.subtag_ids == [2]
+        test_tag1.remove_subtag(2)
+        assert test_tag1.subtag_ids == []
+        test_tag1.remove_subtag(2)
+        assert test_tag1.subtag_ids == []
+
+    def test_debug_name(self, test_tag1, test_tag2):
+        assert test_tag1.debug_name() == "tag1 Name (ID: 1)"
+        assert test_tag2.debug_name() == "tag2 Name (ID: 2)"
+
+    def test_display_name_no_shorthand(self, mock_library, test_tag1, test_tag2):
+        test_tag2.shorthand = ""
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == "tag1 Name (tag2 Name)"
+
+    def test_display_name_with_shorthand(self, mock_library, test_tag1, test_tag2):
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == "tag1 Name (tag2)"
+
+    def test_display_name_no_subtags(self, mock_library, test_tag1):
+        test_tag1.subtag_ids = []
+        result = test_tag1.display_name(mock_library)
+        assert result == "tag1 Name"
+'''
+    #This probably isn't how we want display_names to work. But these tests pass if uncommented
+    def test_display_name_no_name(self, mock_library, test_tag1, test_tag2):
+        test_tag2.name = ""
+        test_tag1.name = ""
+        test_tag2.shorthand = ""
+        test_tag1.shorthand = ""
+
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == " ()"
+
+    def test_display_name_no_name_no_subtag_ids(self, mock_library, test_tag1):
+        test_tag1.name = ""
+        test_tag1.shorthand = ""
+        test_tag1.subtag_ids = []
+
+        result = test_tag1.display_name(mock_library)
+        assert result == ""
+
+    def test_display_name_no_name_with_subtag_name(self, mock_library, test_tag1, test_tag2):
+        test_tag1.name = ""
+        test_tag1.shorthand = ""
+        test_tag1.subtag_ids = [2]
+
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == " (tag2)"
+
+    def test_display_name_no_name_with_subtag_name_no_shorthand(self, mock_library, test_tag1, test_tag2):
+        test_tag1.name = ""
+        test_tag1.shorthand = ""
+        test_tag1.subtag_ids = [2]
+        test_tag2.shorthand = ""
+
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == " (tag2 Name)"
+
+    def test_display_name_2_subtags_no_shorthand(self, mock_library, test_tag1, test_tag2, test_tag3):
+        test_tag2.shorthand = ""
+        test_tag3.shorthand = ""
+        test_tag1.subtag_ids = [2,3]
+
+        mock_library.get_tag.return_value = test_tag2
+        result = test_tag1.display_name(mock_library)
+        assert result == "tag1 Name (tag2 Name)"
+'''
+
+if __name__ == "__main__":
+    pytest.main()
+