A creative tissue is like a check in to see how the creative work is sitting with the client. A tissue is like a WIP. The creatives present the idea and the clients feedback on it with any amends they have. During pitches, tissues work a little differently. You only get one chance to check in with the clients to see if the creative idea is on the right lines. It's a formal presentation and the CEO, CCO, and CSO of the agency may all be present.
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