This thesis deals with the integration of ICT services at the technological level. It mainly focuses on the integration of services which are provided by third parties and a user cannot change them. In this work are described the characteristics of web services and the typical methods for designing their application interface. Furthermore, are described various approaches to integration of applications at the technological level and some integration tools. As part of this thesis, was also created an application designed for integration of web services. This application can be categorized as message-oriented middleware. The aim was to create a simple application, which still meets basic requirements for this kind of applications. This thesis...