The RYA Sail Trim Handbook for Cruisers is an all-new title and is crammed with useful tips and pointers on one of the fundamentals of good seamanship: sail trim. The book focuses more on the needs of the cruising sailor as opposed to the out-and-out racer. After all, a well-trimmed cruising yacht will be better balanced, easier to handle, and will sail more comfortably.
Click the picture to go to the RYA shop and purchase.
I can't find it on there - but I have signed up as an RYA affiliate and get a slightly better rate of comission from them than I do from Amazon.
If you click through from one of my RYA links. There are of course loads of other titles on this subject available from the singlge-breasted ones - you can click through from any Amazon link on here and search for Sail Trim.
(Webcraft's Amazon commission rose above minimum payment level (£25 in a month) for the first time in ages last month, but that was from links on about ten other sites as well as this one . . . .)