Let me guess, you are considering your first digital SLR purchase. There are so many choices - Nikon, Canon, Sony(+/- minolta), Pentax, Samsung, Leica, Olympus, Panasonic, Fuji, Sigma plus any other future attempts to get into SLR market. What to buy? Where to start to research what to buy? First of all it depends what you already have. If you have some specific lenses, flashes and film SLR body, you might consider to reuse all this. But I don't think that you have waited so long to purchase digital SLR. In any case this is a guide for beginners. Or people who consider to switch from one brand to another. You have to understand that SLR brand is something like ecosystem. You don't just buy no-brainer point and shoot and you are done. You buy something with replaceable and upgradeable parts. SLR system consist of 3 primary things: 1 SLR body 2 Lenses 3 Flash/light equipment 4 any additional things. SLR body is most likely to be upgraded in the future. Lenses are most likely to stay for longer time. Flash is also has quite long life. Let's see what is on the market. Old players: Nikon, Canon, Olympus, Pentax. These have been in a market for quite some time, they are quite known for their optic (primary important thing in SLR system). You can add Sony to old players because they bought Minolta and continues on it's legacy. However Minolta was quite weak player in digital SLR market as well as their optic became a little bit outdated in a digital world. Very young players: Samsung and Panasonic. These mostly specialized in point and shoot models. Dead players: Sigma. Kodak Sigma is not innovating. Kodak officially discontinued their efforts in SLR market. OK, let's see what manufacturers offer (currently. Don't forget that old players have old still compatible lenses): Nikon -7 SLR bodies 46+lenses (I didn't counted manual and tilt and shift lenses) 4 flashes so - Nikon 7 B, 46+L, 4 F (including macro) Canon- 8 B, 63+L, 5 F (including macro) Olympus- 3 B , 20 L, 2 F Pentax- 4 B, 22L, 3 F Sony - 4B, 24L, 5 F (including macro) Samsung - 4B, 7L, 1F Panasonic - 2B, 3L. 3F Sigma 1(!)B plenty lenses, but a lot of them made for other brands too. I call Sigma lenses manufacturer, but not SLR manufacturer. 3F There are also 3'd party lenses - Tamron, Tokina for mostly Nikon and Canon. There are 3'd party flashes as well, but you have to note that every respectable manufacturer should provide you with such accessories and there is also compatibility issues in the future. These are technical aspects, with notion that you will get into digital photography more seriously, and use your SLR more than just for digital snapshots. Also I assume that you might grow a little beyond kit lenses (I think that is why you purchase SLR to begin with). So what is the verdict? Canon and Nikon 1'st place. Sony seems quite promising 2'd place together with Pentax. 3'd place is Olympus. Also consider prices. For example Nikon has lover price points for SLR bodies, lenses and flashes (without sacrificing quality) compared with Canon. Canon however offers more full sensor bodies and some better optic (beyond reach for most soccer moms). Other manufacturers offer stuff for even less than Nikon or Canon, but somehow quality or selection suffers. For better stuff they charge sometimes more than Nikon or Canon for similar item.