I'm going to work on a online cession management system. Before I start custom coding it all, I'm trying to see if such system exists already. So, i should explain what a cession management system does. Cession is, by Google: "The formal giving up of rights, property, or territory, esp. by a state." In this case, it's debts, by users. Process of "making a cession": You owe money to person A. Person B gives that much money to person A and buys off the debt. Then you owe money to person B. Person A and person B "made a cession". So, the system will have users. Each user will be able to define other users they owe money to. The system will just show users you can "make cession" with. And that's it. I hope I explained well. If you have an algorithm for this, that would also be great.