Why don't you do some research online:
An Expatriate may only be employed by his or her Sponsor of Residence unless the Labour Department approves a six month secondment. Such secondments will normally only be approved where the subject matter of the work to be undertaken is, or both entities have a shareholder in, common, eg. a lawyer being seconded to a client to undertake legal work or an employee being reassigned to a sister company. In some cases the Labour Department will approve an Expatriate working for an individual or entity other than his or her Sponsor of Residence if such work is undertaken outside normal work hours.

Secondment still falls under the category for NOC requirement! If you are still puzzled, check with immigration at Gharaffa - There is your valuable advice!

http://portal.www.gov.qa/wps/portal/!ut/p/a0/RY2xDsIwEEO_hSFzUtjYKhaQ2Bi...