With the Internet now being a part of everyday life mixed-mode surveys that use the world wide web can be seen as an opportunity to increase the response rate of surveys. This paper looks at the advantages and disadvantages of different response modes suitable for mixed-mode surveys. Based on this consideration the paper addresses the influence of a mixed-mode approach using conventional mail and web based questionnaires on coverage, sampling, measurement, and non-response error as well as pitfalls and opportunities specific to this type of survey. It discusses mixed-mode and web specific issues such as technological aspects, security, convenience and similarity. The paper proposes that this approach has no apparent potential error consequences if certain requirements are fulfilled. The use of mixed mode questionnaires is exemplified by a survey conducted with 1000 SMEs in the North West of England in 2002. After analysing the findings the paper concludes by looking at the relation between the mode of response and the answers provided by the respondents and by summarising the insights gained from the study.