Research to date on negotiation protocols has focused almost exclusively on defining simple contracts consisting of one or a few independent issues and a relatively small number of possible contracts. Many real-world contracts, in contrast, are much more complex, consisting of multiple interdependent issues and intractably large contract spaces. The family of negotiation protocols we've developed make substantial progress toward achieving near-optimal outcomes for negotiations with binary issue dependencies. We propose a simulated annealing-based approach, a refined version based on a parity-maintaining annealing mediator, and an unmediated version of the negotiation protocol.