I use ActiveCollab as a member of the research group for the management of my ongoing projects. It is a very convenient tool, that allows me showing the other member of the group my progress, intermediate results, final manuscripts.

We migrated to Active Collab abount 2 months ago after attempting to work with Basecamp, Trello, and NutCache. The combination of project management, team+client collaboration, time tracking, expense tracking, and project templates, API, and accounting add-on integrations made this hard to beat. The UX is also the best that we've come across.

retainer-based clients where they are paying a fixed monthly fee for our services.