To qualify for this study we are looking for individuals who have psoriasis on at least 10% of their body. The way that you measure this is to place an open hand, with fingers together, over the affected area. Each time that you can completely cover an area, that will represent 1% of your body surface area. If you can place your hand and cover the psoriasis 10 times (in different areas) then you have at least 10% body coverage. This study is usually for patients with plaque psoriasis.