Within Teamwork Projects, you can quickly view the details of the company associated with a project from within the project itself.
No matter which area of an individual project you are viewing, you can view the company's information by hovering over the company to the right of the project name:
In the pop up modal, clicking the company name at the top will bring you directly to the full company view in the People section.
You can also view a list of the projects associated with the company here, and click into each one directly from the modal.
For more information, see: Adding or editing a company