The workshop proceedings of International Cooperation on Theories and Concepts in Traffic Safety (ICTCT), held in Helsinki and Tallinn, October 1992 is presented. The workshop covers. (1) Formulation of sustainable transport systems, including road safety aspects: (2) Matters such as the usefulness of conflict observation as a diagnostic and evaluation technique in the short term for existing and proposed infrastructural measures; and (3)The use of other methods of evaluating road safety measures, such as questionnaires, interviews and accident analysis. The following papers are included: Bridges between policy and research (Kray,H); International co-operation on exchanging data and knowledge for road safety management (Mortelmans,J); How to educate our decision-makers: A challenge for researchers (Muhlrad,N); A framework for the prediction of the road safety effects of new technology (Janssen, W and von der Horst,R); Traffic conflicts as indicators of pedestrian safety in a DRIVE project (Draskoczy,M); The effects of speed limiters of heavy vehicles - a traffic simulation study (Kulmala,R and Beilinson,L); The speed limiter in the car for safer traffic and better social climate in the cities (Hyden,C); Varying speed limits based on weather conditions (Pajunen,K, Maenttaeri,J and Almquist,S); Evaluation of driver workload during a simulated and an actual driving task (Malaterre,G); What can we learn from drivers behaviour and accidents in order to discuss the relevance of new technologies (Saad,F and Fleury,D); Future safety gains and safety problems connected to new technologies (Chaloupka,C); Video recording of traffic accidents (Pasanen,E); cardiovascular diseases and traffic safety (Elgarov,A); Drivers emotional reactions in conflict situations on roads (Vaisman,AI and Volper,GI); Interaction between cyclists and car drivers: which role could technology play (Schmidt,L); A study of the behaviour of drivers of electric minicars (Risser, R and Stockinger,M); The pedagogical use of traffic conflict technique (Zuzan,W); Monitoring traffic behaviour in the context of an evaluation of a national traffic police force (Zaidel,D, Hocherman,I and Hakkert,S).