[Rimrock66]

 I was wondering if you are making a yeast starter with Wyeast, do you need to smack the pack and let it activate before adding to starter?

[Wort-H.O.G.]

I was wondering if you are making a yeast starter with Wyeast, do you need to smack the pack and let it activate before adding to starter?

yes there's a small pouch inside that you can feel and push to a corner, then press firmly down on it and it will pop. not an absolute but best practice to do so.

[Stevie]

I do smack it and will let it swell sometimes, but often just smack, shake and pitch into the cooled starter.

[denny]

I was wondering if you are making a yeast starter with Wyeast, do you need to smack the pack and let it activate before adding to starter?

Nope, you don't.  That's just an indicator of viability.  You'll see that when you make a starter.