A very fine response by Louis Proyect to an advocate of "cadre-style" party building.
I've been enjoying Proyect's contributions on this question recently, due to his recent "Kautskyite" turn, which mirrors my own perspective around building Die Linke.
http://louisproyect.wordpress.com/2011/12/23/what-kind-of-party-do-we-need-a-reply-to-ahmed-shawki/