diff --git a/requirements.txt b/requirements.txt
index c56e497..0b08307 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,27 +20,29 @@
 
 virtualenv
 
-flake8==7.2.0
+flake8>=3.8.2,<=7.2.0
 pexpect==4.9.0
-pre-commit==4.2.0
-pylint==3.3.6
-yamllint==1.37.0
+pre-commit>=2.5.2,<=4.2.0
+pylint>=2.5.2,<=3.3.6
+yamllint>=1.23.0,<=1.37.0
 
 # -----------------------------------------------------------------------
 # https://pypi.org/project/robotframework/#history
 # -----------------------------------------------------------------------
-robotframework==7.2.2
+robotframework>=3.1.2,<=7.2.2
 robotframework-importresource==0.2.0
 robotframework-kafkalibrary==0.0.3
 robotframework-lint==1.1
 robotframework-requests==0.9.7
-robotframework-robocop==6.0.3
+robotframework-robocop>=5.5.0,<=6.0.3
 robotframework-sshlibrary==3.8.0
-robotframework-tidy==4.16.0
 cord-robot==2.1.10
 
-matplotlib==3.10.1
-requests==2.32.3
+# Cannot be included until after tests are moved past Ubuntu 18.04/Python 3.8
+# robotframework-tidy==4.16.0
+
+matplotlib>=3.3.4,<=3.10.1
+requests>=2.24.0,<=2.32.3
 grpcio<=1.39.0  # Required for voltha-protos
 grpc-robot>=2.9.3
 kafka-robot>=2.3.2