ROI is an economical concept apllied into a many fields to measure efficency of some actions or activities. Education and training domanin has a own rules to measure the results and to see if the objectives were fulfilied or not, all concentrated arround the concept of educational efectiveness. Speaking in terms of technologicaly based learning, besides the educational effectiveness many managers and decisions makers want to know if the investenment into a new system is efficient or not. This paper will try to explain the role of the economical view into the decision making process in the dducation and training domains with focus on the return of investemnt metrics. Since the e-learning technologies entered into our life a questions is persistent- It is worth to be implemented? The answer is not simple and is not bipolllar, yes or not! Return of investement could be a strong suport in decision by providing an economical point of view. But also, we encounter another question - education is only money? As conclusion, the ROI has to put onto the some formula both educational efectiveness in terms of knowledge or skills aquisition and the money spent for that. Of course that as in any economical calculation, there is an marginal efficency and this has to be taken into consideration, also. Finally, the paper will bring into atention a study case and a proposal for a calculation. The study case is National Defence University experienced based and is adult learning in the military field oriented.

E-learning, return of investment, educational efectuveness