To remove members from your company you need to first access your company members tab by clicking the little person icon in the upper right corner of the screen:
Once inside the 'members' page, you'll see a list of all your company's members and their permission levels.
To delete a tem member, click on the trash can icon next to their permission level and confirm.
That's it, the team member has been deleted from your company!
Attention: Whenever you delete a member from your company, everything he/she created (pipes, cards, etc.) will still exist.