Financial sources of the SLO are: donations, inheritances, legacies, research grants from foundations and institutions, and sponsoring by (medical-pharmaceutical) companies. The latter source is the most important one, and has a dual character.

On the one hand the SLO participates in industry-initiated studies, for which it receives funds to appoint staff and to cover other costs.

On the other hand the SLO itself actively recruits funding to initiate to SLO-initiated research. In these studies, which are after international, SLO acts as a sponsor of the study.

The SLO has a special focus on the latter type of research.