Three major objectives were established for this study of mode-choice decisions affecting inter-city travel. They were: (1) the collection of basic information on mode-choice decisions, (2) an examination of the common belief that individuals with similar characteristics reveal similar attitudes, perceptions and decision-making processes, and (3) the development and testing of an integrated model of individual decision behaviour to see if mode-choice decisions could be reproduced from measurements of mode images. Data were collected in Malaya during 1970 by means of two questionnaire surveys. One set of questionnaires was distributed to travellers making inter-city journeys and sought information on their awareness of alternative modes of transport and on the criteria used to evaluate them. The second survey was conducted among informal groups of respondents and used a semantic differential to measure images held of modes of transport. Data were also collected on the relative importance that respondents associated with particular mode attributes and their mode preferences for a specified journey, Analyses of these data showed that: (1) fewer than half of the travellers were fully aware of the objective choice context, (2) travellers used a wide range of criteria to evaluate modes but concentrated mainly on matters of safety, cost and travel time, (3) the semantic differential generated summary mode images that were distinct one from another and highlighted major points of perceived similarity and contrast between modes, (4) the knowledge that travellers held of the cost, duration and distance of their journeys was often highly inaccurate and (5) the tested aspects of the mode choice decision were not strongly related to the character istics of respondents. Several simple numerical models were used in attempts to reproduce the mode preferences reported by each respondent from the measurements made of his or her mode images. These models showed that more than forty percent of the decisions could be correctly predicted. A critical review of the conceptual framework and operational procedures used in this study examined their relevance for research in behavioural geography.