After her auditing duties as the Tax Inspector in Tax Inspection Board of Turkish Ministry of Finance, from 1992 to 1996; Ümmiye Aytaş Kösoğlu also served as a tax director in international audit firms between 1996 and 2009.

Ümmiye Aytaş Kösoğlu, who has participated in drafting some of the laws along with officials from the Ministry in 2005, joined Moore Turkey as Director in December 2010.