You may add unlimited number of contributors to your project. User roles include admin, translator and proofreader. Click project's Contributors icon to begin.
Project admins have full read/write access to all project languages, however can have limited access to project features.
Translators have limited access to your project, and have a simplified UI too. Translators are granted with reference (read-only) and/or contributable (read-write) access to your project languages (adjusted language by language).
Both admins and translators can be also granted a proofreader role. This role becomes available once you enable Proofreading in project settings. Users with proofreader role enabled are able to mark translations as proofread in the editor and approve any translation, in case translation upvoting is enabled in project settings as well.