Obtaining visas or work permits for Thailand is a transparent, streamlined and quick process.  To understand which entry documents apply to your needs please review the following: 

Non-Immigrant 'B' Visas 
If entering Thailand for business purposes, the Immigration Department requires a non-immigrant Business or ‘B’ visa. Application for this visa must be made outside of Thailand. For further information on how to apply for the visa, please refer to Ministry of Foreign Affairs. Click here

Work Permit
Non-Thais must obtain a work permit prior to working in Thailand in accordance to Alien ACT B.E. 2551. A prospective employer or sponsor must file the application for the work permit with the Ministry of Labor and a non-immigrant visa must be obtained from a Thai Embassy or Consulate before the work permit application is filed. For more information on applying for a work permit, please refer to Office of Foreign Workers Administration, Department of Employment. 

Promoted companies may bring in foreign nationals such as skilled technicians or experts, with their families, by contacting the BOI regional office or the One Stop Service Center for Visas and Work Permits.