The work of SECI would not have been a success without the invariable voluntary financial contributions from its supporting States. From its inception, Austria, Italy, Switzerland and the United States have supported the work of the SECI Office of the Coordinator in Vienna with their voluntary financial contributions to the Secretariat as much as to the various projects developed within the framework of the initiative. Thus, besides financial support, supporting states have provided SECI with valuable technical expertise and assistance for its project groups, most notably the border crossing facilitation efforts. The Austrian Federal Ministry of Agriculture and Forestry played an instrumental role in hosting and coordinating the SECI Recovery Program for Rivers, Lakes and Adjacent Seas. Former Vice-chancellor of Austria and SECI Coordinator, Dr. Erhard Busek, is actively working towards involving Austria in every aspect of SECI. The Czech Republic and the Netherlands joined SECI as supporting states. The Czech Republic decided also to contribute financially to the implementation of the sub-project on the development of the "Tele-information System among national Dispatch Centers in Southeast Europe". In the past, representatives from the European Union Presidency and the Russian Federation have been regularly invited to the SECI Agenda Committee meetings and have also observed some project group meetings. This practice is still observed through the participation of such observers to the various meetings within the main projects of the Office of the Coordinator and the SECI Affiliated Structuresas well as through their regular updating on the SECI activities. 

Last, but not least, SECI States, such as Greece, Romania and the former Yugoslav Republic of Macedonia have not long ago decided to join the group of supporting states by making voluntary financial contributions related to the SECI activities.