Summary: The paper evaluates the impact of the complexity approach on economics from two viepoints. On the one hand, the dissolution of the shared notion of mainstream, which began in the mid ‘80s. Until then, the Samuelsonian paradigm had been able to absorb those contributions that critically challenged its assumptions and results. This process took place at the expense of gradually blurring the boundaries of the paradigm itself, which has lead to speak of its dissolution. The emergence of complexity theory raises the need to either extend further the boundaries of the old paradigm so as to close the gap between apparently irreconcilable differences or to define a new one. On the other hand, it is legitimate wonder to what extent complexity theory qualifies as a ‘paradigm’ and thus whether it can be a candidate for substituting the Samuelsonian paradigm.