Yes, the Royal Canin Urinary S/O is a prescription diet so you have to buy it through your vet. The Innova Evo can be bought at most independent pet stores. They usually carry the dry and the Turkey/Chicken kitten/cat formula in the canned food. Some will carry some of the 95% meat canned foods and they come in Venison,Beef, Duck, and the Chicken & Turkey flavors. I had to have the store special order the 95% Chicken & Turkey and I bought 2 cases and the store also gives me a discount per case.

Here's the website for the Royal Canin Urinary S/O Formula:http://www.walthamusa.com/Learning%20Center/SO30.html.

Here's the website that tells more about Innova Evo: http://www.evopet.com/products/default.asp?id=1662. You can also click on the link where to buy and it will list the pet stores in your area that sell it. Good luck.