Topic of this master thesis is “Knowledge recording and communication support in complex design project”. Research part of this thesis was conducted on the example of EGPR 2015 project. This project was source of information needed for knowledge recording and traceability. It also provided an insight in communication processes that took place in a complex international development project. With this thesis different design issues were identified and possibilities of knowledge recording using IBIS diagrams were studied. Knowledge from the project was recorded using those diagrams. Also, communication between participants of the project was analysed to gather existing issues within a diverse environment. Different flows of communication were recorded as well as issues with communication process that occurred. During the project communication was supported by introducing a virtual white board tool for communication and collaboration. After the project ended, knowledge and communication were analysed and different improvements were suggested for use in similar future complex development projects. End of this thesis was dedicated to traceability. Relations of traceability were made and analysed together with possibilities of recording and usage of traceability.