Spread the love Headquarters: 7361 Calhoun Place, Suite 560, Rockville (Derwood for GPS), MD 20855, USA, Metro Park North Business Center. Check our Visitor Guide for location details, driving directions, nearby hotels and restaurants, and more. Phone: 301-384-3350 E-mail: service@ostglobalsolutions.com Share this:Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Tumblr (Opens in new window)Click to share on Skype (Opens in new window)