In 2015 the Trans-O-MIM research project was launched with the intention to identify and explore solutions in transforming subscription-based journals into Open Access journals. Trans-O-MIM stands for strategies, models and evaluation metrics for the goal-oriented, stepwise, sustainable and fair transformation of established subscription-based scientific journals into Open-Access-based journals with Methods of Information in Medicine as example. Results are presented on the experiences made so far with the Open Access transformation of Methods of Information in Medicine by implementing a so-called Tandem Model and on major results on drivers and obstacles of Open Access publishing, obtained from the three empirical studies, in which the perspectives of medical informatics researchers of IMIA member societies have been explored.