Hi Mark, it's true what Iain says that you cannot hide lists on a board.
As a workaround, I would suggest you set up a second board that only your clients are able to see and find a way to sync those cards/lists with the board of origin.
This can happen with the Butler Power-Up for instance. But there are other Power-Ups that do a pretty good syncing job.
This way, you can have one board that your employees use and update and an extract of that board displayed on a separate board with access to your clients.
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events