According to applicable local regulations as well as the Good Clinical Practice (ICH GCP R2 and R3) there is no obstacle for the sponsor/CRO to use the services of a Site Management Organization (SMO) as service provider. The roles and relationships between the service provider and the investigator/institution/sponsor have been clarified in ICH GCP R3, which has further facilitated the work in clinical studies for this type of activity (points 2.3. and 3.6 of the guideline). The conditions for using SMO services in the Republic of Serbia are defined by the sponsor/CRO, institution and investigator (contracts, training, oversight, etc.), all in accordance with the relevant points of ICH GCP R2/R3, which has been adopted and is part of local regulations.