"The first rule is we will never vote for something that we don't agree with," Patrick says. "And we will always vote for something that we have a strong agreement with." When legislation is grey, things get interesting. "There might be some benefits in the piece of legislation or some downsides, and we will almost always try to seek amendments to draw the final outcome into the centre," he says of negotiations. Always in mind are five key rules: good faith, confidentiality ("so that all options can be properly explored"), respect ("including when an agreement is not reached"), trust ("agreements are honoured") and knowledge.

"We won't negotiate without proper briefs from stakeholders on both sides of the question," Patrick says. "Or a Senate inquiry that can tease out all perspectives and unintended consequences." Centre Alliance have said they might support the tax cuts that are first on the government's post-election agenda, for instance, but need to work through the policy effects - meaning there remains a chance the nature of the cuts will be determined in fierce episodes of negotiation with Cormann, the government's leader in the Senate. The working relationship between these two men is perhaps one of the most important in the country. Credit:Alex Ellinghausen Such negotiations are nothing new to Patrick, and while they may be fierce, they're always honest, he says. "One of things about working with Mathias was the ability to sit down with him at the start and say this is where we sit. We would say there is no way we would vote for this legislation, and in almost all circumstances he would accept that.

Loading Patrick says he learnt how to negotiate as an adviser to Xenophon - a master arbiter who bartered hard with the Turnbull government over its flagship company tax cut legislation. "Government negotiators sometimes can't quite believe what they are having to give him," it was written at the time. Patrick developed his negotiation rule book after that "very, very tense negotiation" experience. "There were two other things that occurred - one of them was goodwill. That meant never betraying one another. You often saw Mathias standing up and saying 'I'm not going to talk about the conversations we've had with the crossbench' and that was a healthy way of conducting negotiations.

"The second thing was that not all negotiations were necessarily related to a bill - sometimes we could go to Mathias and say to him 'this is something that's really important to us, it's not a huge cost, would you consider it?' And from a goodwill perspective he would say 'yes, I can get that done for you'." Patrick points to the small change - in effect from 1 July - that allows journalists to conduct company searches without fee as one such gesture. This time around, on the top of Patrick's negotiating to-do list for this term of government is the Murray-Darling system and water management. He continues to call for a royal commission into the basin, and says he will push the government to act in exchange for support on key legislation. And even when he and Cormann staunchly disagree, like with water policy, each still takes effort to maintain a friendly relationship. "Yes, there's been times when Stirling and I have sat down at the end of the week and had a beer with Mathias," Patrick says.