Cynhaliwyd Cais am Dystiolaeth rhwng 16 Mai a 21 Mehefin i geisio barn ar y modd y gall defnyddio’r Gymraeg a dwyieithrwydd gefnogi twf busnesau a datblygu economaidd, a sut y gallai datblygu economaidd gefnogi cynnydd yn y defnydd o’r Gymraeg. Daeth ymatebion i law gan grwpiau o fyd diwydiant, grwpiau a diddordeb yn y Gymraeg, busnesau ac unigolion.
A Call for Evidence was held between 16 May and 21 June seeking views on how the use of the Welsh language and bilingualism can support business growth and economic development, and how economic development could support increased use of the Welsh language.   Responses were received from industry groups, groups with an interest in the Welsh language, businesses and individuals.