Did your company just undergo a move? Have you changed owners? If you ever need to change your Company information (including address, company name, industry, size and owner) you can do so by clicking Settings from the main toolbar on the left. From there, click Company Info:
This will take you to the Company Information page, where you can update information specifically regarding your company.
Are you looking to change contact details for yourself or another user? You can find out how to do that in our User Information page.