Thank you Lucie, this clarifies a lot for me.

I already took a look at the website of stichting marketing (http://www.stichtingmarketing.be).

Hi, Marketing is a toolbox, indeed, and social profit marketing has a set of somewhat altered tools to match the particular content and goals of social profit organisations. Not in the least, much effort goes in the 'marketing of marketing' within the social profit setting, meaning that a lot of 'translating' between the two worlds has to be done. So social profit marketing could mean the marketing of social profit content as well as the marketing to the social profit sector.
more info: stichting marketing, expertgroep not for profit marketing

Hello Lucie, could you explain to me, what the difference is between social profit marketing and marketing? I wonder, because I would think that marketing is a tool, that can be used in any situation if that may be for profit of not for profit or for social profit.