Although the Admiralty pilots have been regularly revised every 10 to 12 years as well as being kept corrected by supplement, there has been remarkably little change in the general style and content for over 100 years. As a major step has recently been taken to modernize and metricate the Admiralty chart, it was considered opportune to study the pilots at the same time. Therefore towards the end of 1968 a small committee was formed within the Hydrographic Department to review these books. The first action by the committee was to initiate some market research. All members of the Chart Users' Panel were invited to answer a questionnaire of twelve questions, but a few weeks later it was considered desirable to spread the research over a wider field and the same questions were sent out as a Notice to Mariners (No. 1737/68). The response was most encouraging and by the closing date at the end of December about 780 replies had been received and these have all been analysed. A few replies still come in, which puts the total at over 800$quite a good proportion of the regular users.