German to Spanish Bus/Financial Human Resources Non-Governmental, non-profit sector

I am looking for the best Spanish equivalent ("director"? "gerente"?) of the term "Geschäftsführer" which,in this case, applies to an NGO (absolutely non-profit).Said NGO has a President and a "Geschäftsführer", the latter taking care of all current matters. "Director ejecutivo"seems appealing, but I hesitate using it since the organisation doesn't have any other kind of "director". Thanks in advance for any help!
PS I have read all the relevant KudoZ answers and there seem to be arguments in favour of any possible option. I'll therefore go ahead with my question, asking the colleagues to kindly provide their opinions bearing in mind the context I specified.
Vielen Dank im Voraus/Muchas gracias de antemano,
Cristian