I am looking for contracts via an agency. Would this alone place me within IR35?

Some agencies specify that the end clients insist on contractors paying PAYE on their income and therefore they word employment contracts in such a way that the contractor would fall within IR35. By agreeing to these terms within the contract you would be changing the working practice. However, some agencies are happy for you to personally negotiate terms within the contract and providing the nature of the contract work is that of self-employment then IR35 would not apply. The key is understanding how the contract will be fulfilled, and then to word a contract that reflects that when negotiating with your client.