Few naturalistic studies have been carried out with commuter cyclists to discover the types of problems they encounter on a daily basis. The study presented here has been commissioned by the City of Stockholm municipality and focuses specifically on commuter cyclists in the Greater Stockholm area. The aim of the study was to describe and pinpoint accessibility and safety problems, but also to generate an accessible geographical interface that could serve as a traffic planning tool for cycle network improvement. Statistical surveys in the Stockholm area have shown a rapid growth in the number of cyclists as well as an increase in problems associated with an overburdened cycle infrastructure. Given the heightened emphasis on transport system sustainability, the City of Stockholm is faced with the challenging task of trying to maintain and encourage the upward trend in commuter cycling through a process that involves problem identification, classification, prioritisation and resolution. An innovative methodology involving the use of GPS logging devices and small video cameras was developed and supported with analysis software designed specifically for the purposes of this study. Experienced commuter cyclists were recruited to cycle 17 different major cycle routes to and from the suburbs and inner city area during morning and afternoon peak traffic hours during the main cycle season. Over 500 safety and accessibility/mobility problems were identified and recorded from the data collected from 16 commuter cyclists. The method and representation of data proved successful for strategic traffic planning work at City of Stockholm and has since provided invaluable input for and the development of a new cycle plan for Greater Stockholm. Indirectly, the results of this work have also contributed to longer term safety and environmental targets.