With the development of digital technology and especially the possibilities for electronic publishing Open access publishing is becoming more and more a global phenomenon. Open access means unrestricted online access to scholarly research and research data. The paper presents the common definitions, the types and vehicles for delivering Open access to scientific publications. Because of its economic efficiency, the potential economic benefits of Open access might have an impact on many other groups besides the users and the authors themselves – publishers, scientific institutions, specific industries, etc. Economic effects of OA are analysed through the concept of its benefits which could generally be divided into two groups – individual and collective. Besides the economic benefits, one must also consider the “price” of OA, as well as its limitations. Together with the effects of Open access that support the development of science, its use could be regarded as a means to increase social welfare as well.