According to About.com's Guide to Sexuality, BDSM stands for bondage, discipline, dominance, submission, sadim and masochism. (see: What Is BDSM?) For anyone looking to date with a BDSM slant, you probably already have a good idea as to what the term means and where you fit into the spectrum. If not, that's acceptable too, since most reputable BDSM personals offer some information and basic information about the lifestyle.
Yet there aren't a lot of BDSM dating websites available today, mostly because it's a smaller market for dating singles and a few well-known brands have almost cornered the market. If you've used one of these dating sites, please share your experiences so as to assist other readers with which BDSM site is best for their needs: Review BDSM Personals Sites
Note: all of these dating sites are meant for adults only, and many display adult-oriented images. Although none listed here showed pornographic materials that I found, these sites may upset some readers. Please click at your own risk, and only if you've reached the age of majority in your geographic location.
ALT.com and Adult Friend Finder share the same database of members, so you'll see the same folks (for the most part) on each site. The differences however, are considerable, when looking at BDSM relationships and merely adult, casual ones: ALT offers a huge number of questions to determine your specific kink, and each one is easily searched by its paying members. For those not willing to pay the (somewhat steep) fees, try hanging out in the groups or chat rooms to see if someone nearby shares your interests.
IWantU.com offers a section specifically geared towards alternative relationships. Do keep in mind however that since the database of users is shared with other members on the IWantU.com platform, not all members will post BDSM personals.
More of an adult dating site than BDSM, SexyAds does offer some functionality for kinky folks too. Note that the default for all new, unpaid users is "good", where you can only look at tame photos. View all the 'wicked' pictures by upgrading and paying for a membership.
A networking group for BDSM singles in the New York area. Only open to those over the age of 18. Offers munches, education, training and support for kinky folks, both single and otherwise. A great, safe way of meeting other BDSM lovers, but because it's only available to a small geographical location, it ends up lower on this list.
A racy front page welcomes BDSM singles from all over the world, but the site focuses primarily on the US. No ability to read the site's policies and procedures without signing up first, which concerned me, and therefore why it ends up toward the bottom of this list.
A dating site catering not the the richest of alternative singles, but rather to a rich experience with meeting other BDSM lovers, even if that's a couple or group.