With the dawn of the internet, mobile technology, cloud computing etc. our socio-technical environment has become ever more intertwined and hyper-complex. The field of complexity management tries to devise methods and methodologies to cope with the challenges arising from complexity. This chapter provides a brief overview of the field of complexity management. More specifically, it defines in detail the terms complexity and dynamic complexity. Dynamic complexity is most relevant for high impact decisions and I examine two methods First, causal context modelling (CCM). This is an integrative, qualitative, transdisciplinary approach which creates a qualitative description of a system including key variable interdependencies and system boundaries. The second methodology I explore is system dynamics (SD). Here I provide examples from a project carried out within the Use-it-Wisely project which helped the companies involved understand and deal with the dynamic problems facing them.