Eris Solver is a free crowd-solver for complex problems. It implements an innovative way to solve complex problems by adapting brainstorming technique to a Problem Tree Analysis and by channelling Collective Intelligence. When simple problem may require a unique solution to be solved, Complex problems behave differently and multiple solutions are sometimes necessary to solve them. On the contrary to simple problem that may not need further deepening, a complex problem may be broken up in multiple small ones that help us understand the big picture. Every branch of the issue tree represent a different aspect of the problem, problems can be decomposed this way until reaching the bottom line where solutions to the ultimate sub-issues are added. Eris Solver uses an interdisciplinary approach and users are allocated into six major areas of expertise