This is from "America's Knitting Book" - which I have found to be correct about everything I have ever consulted it about ... 1. If you must use a device to count your rows, a) do not count the cast-on row b) do not increase the count until a partly worked row is completed c)do not use a needle-mounted counter-string such counters on yarn and fasten the yarn to your work 2. Try not to count your rows, measure instead (pieces to be joined may vary in gauge, and even though they have the same number of worked rows, they may not be the same size) 3. If you have not used a device to count your rows, are working in stockinette, and feel you need to know how many rows have been done, count the "bumps" in vertical columns on the purl side. apart from this "rule", any method is okay.