Of course, there are many different options, and many different business models. Some work for some firms, and others do not. My suspicion is that some of those attending the session are going to be looking for definitive solutions. And, of course, there aren't any.
The secret lies in the ability of professionals around the world to develop close and cooperative relationships with those with whom they want to do business, whether the international structure is formal and rigid, or informal and fluid. Depending on the nature of the structure, those relationships may need to be created or nurtured in different ways, but there will be a way, and it is the responsibility of the individual to find and pursue it.
If your firm is not yet in some sort of international grouping, but sees that route as its logical next step, then please don't become too blinkered by size and promises of referral business, or, worse still, attracted by the exotic location of the next international conference. Instead, ask yourself two very basic questions:
How am I going to establish and maintain relationships with these people?
Are these people that I (and my clients) would enjoy working with?
There are plenty of ways of developing an international practice. Doing so through an established network may well be a good solution. But it is not the only one. And, if it is, having joined the group, you will still have to work hard to make the relationships work.