Find the closest Pantone Color Swatch in Photoshop and Illustrator
Finding the closest PMS color in Photoshop is pretty easy. From the Color Picker, just click on the Color Libraries button and Photoshop will select the closest equivalent Pantone color swatch. Doing the same thing is a bit more complicated in Illustrator, but it also has the potential to do more. basically, you need to use the Live Color feature to reassign existing colors, and limit it to the a particular color book. This is good because it lets you assign multiple spot colors at once.