If you have a citizenship of a country and willing to work for a Qatari company,then you can easily get a Qatar business visa.The concerned company is accountable for organizing business visas for their workers.Business visas normally valid for 2 weeks,which can be expandable on circumstances.
You will need an exit visa to leave, if you stay in Qatar for 4 weeks on a business visa.Purpose of business visa is to stay in Qatar for a short period of time for work or business deals.Visa on arrival is alo available in Qatar for 72 hours as well.It needs a valid return ticket and a sponsoring company letter.
One month long business visas for workers on short term contract and employess from outside also is there.These visa can be extended for three months and a certain amont of fee to be paid.