Currently, tourist destinations are, more than ever, confronted with specific challenges and also negative impacts arising from overarching developments. In order to address such challenges and to reduce negative impacts resulting from tourism, sustainable development has emerged as a widely accepted approach. Under special consideration of seemingly successful destinations, this article aims to identify complementary strategies towards sustainability in tourism, instead of developing completely new strategies which replace the existing ones. This will be done in the course of endogenous values and structures within a destination. To discuss this issue, the Canary island of Lanzarote is used as case in point, via a qualitative interview series consisting of eleven interviews with different direct and indirect tourism stakeholders from the island, which have been evaluated according to the GABEK®-method (German abbreviation for “GAnzheitliche BEwältigung von Komplexität”: holistic coping of complexity). The results show that aspects of mass tourism have a negative impact on the island and therefore a seemingly successful destination, at least in quantitative terms, is confronted with issues of sustainability and a need for action. In this field, diversification regarding both new offers and target groups is helpful to enable tourism and regional development to be more sustainable. In consequence and from a conceptual point of view, alternative product development as a new approach towards sustainability in tourism within established destinations will be presented.