What you need to do
For complex procurements where the negotiated route can be justified, contract negotiations are time-consuming and intensive but are key to the success of the project in achieving the right deal with the right supplier. Planning is essential to ensure they stay on track. Identify the order in which parts of the contract are to be tackled, the review points, and who is involved in developing and reviewing them.
Identify specialist resources, legal, financial, technical etc and ensure they are available when required.
There will be a lot of documents exchanged with suppliers, so ensure there is a configuration management plan in place to cover version control, routing, storage etc, and resources to implement and manage it.