INTENSE (INTElligent Non-linear Systems of Equations solver) is a problem-solving environment that provides the computational facilities necessary to find a numerical solution for two classes of problems: ordinary differential equations solving and non-linear algebraic simultaneous equations. INTENSE proposes facilities like a friendly user interface for problem specification, the automatic detection of the problem properties, a friendly user interface for the methods specification, the automatic detection of the method properties, a matching mechanism between the problem properties and the method properties, apply the numerical method and supervise the error, some lists or graphics of approximate solution values, solve the problem without the specification of a particular method.