If it's got a silver emblem on the back, you have a smart key system (SKS) and you should buy this key

and it's a fully-functioning backup key WITH the smart key system

I have a 2007 Prius with the Smart Key System and used the chicken dance instructions

With Smart Entry System arrived in perfect condition and shipped promptly.

Put the new key in the slot and press Power (start).To program for a Smart Key System (SKS) proximity door locks and keyless start:1

I have a 2007 Prius with the Smart Key System

this smart key will not work with my 2005 Prius that does not have a smart key system.

If yours is SILVER you have a smart key system (SKS)

I wasn't aware that my 04 Prius was not a Smart Key System

I DID succeed though and now have a fully functioning key which locks/unlocks (with the smart entry system too) as well as starts the car

2008 Prius with smart system

Just bought this OEM Key fob with Smart-Key functionality for my 2007 Prius with the Smart-key system

Take note for the reprogramming of the smart entry system you will need a working key

The Prius remote with smart entry key system works perfectly.

I bought this key and followed the chicken dance programming instructions on PriuschatIt took me about 15 minutes, and my new key's smart-key system worked perfectly