Context and setting During our 5-year programme students are assessed by a large number of health care professionals who are geographically dispersed throughout the south-west of England. It is essential that professionals receive training to familiarise themselves with the assessment instruments and marking schemes, participate in bench-marking sessions and receive instruction on how to reliably assess and provide constructive feedback to students to enhance their learning. We developed an assessment website containing interactive tutorials that could take the place of face-to-face training sessions. We describe the results of a first-round evaluation of the utility of the online training resource. Why the idea was necessary The number of health care professionals involved in the assessment process has risen every year, and currently stands in excess of 200. From early experiences we learnt that organising traditional face-to-face training sessions was difficult with such large numbers of dispersed and busy practitioners. We considered that face-to-face sessions could be replaced by online tutorials that could be worked through at a time and place convenient to the professionals. Discussions with other universities and an Internet search uncovered numerous teaching and learning resources, but a dearth of assessment-related resources. We therefore sought to develop a website that could serve as a permanent resource on good assessment practice. What was done The assessment website consists of 4 tutorials, a glossary of assessment-related terms and a reference list. Each tutorial can be completed within 15–20 minutes, and combines subject information with formative assessment, usually in the form of a short quiz, to test the user's understanding. The fourth tutorial incorporates a database where users can provide marks and feedback on a short essay and view the feedback given by other users. The tutorials were developed using the multimedia authoring tool Macromedia Flash, allowing us to combine text, imagery and animations. A re-useable template was used so that future tutorials, on peer assessment, for example, could be easily added to the current collection. Evaluation of results and impact A small number of practitioners and individuals from the school (11) were invited to complete the tutorials and an online evaluation and feedback form. The evaluation consisted of 4 items that explored the usability and utility of the resource using a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree), and 3 free text items. This constituted a first-round evaluation, primarily to identify any problems and determine what improvements could be made before offering the resource to the practitioner population. The responses of the 11 participants were overwhelmingly positive. All participants agreed or strongly agreed that the tutorials were easy to use, that the images and interactive elements were relevant to the subject matter, and that they would feel confident about assessing students after completing the tutorials. Three participants commented that it was a useful learning resource, giving good insights into assessment-related issues. Our experience suggests that online tutorials may be a convenient means of introducing health care professionals to assessment.