Companies in the 21st century are exposed to a variety of pressures to respond to a plethora of environmental issues. Understanding how these issues impact companies over time is, therefore, important for corporate practitioners and policy makers alike. This thesis investigates the state and evolution of corporate environmental strategy with the help of a multi-study, longitudinal research design. Theoretically grounded in complexity theory, a conceptual framework is developed that portrays organisations as open systems within which agents interact and attempt to improve organisational fitness. By conceptualising the organisational metaphor of ‘rugged fitness landscapes’, firms are depicted as complex adaptive systems searching for peaks on a constantly changing fitness landscape in order to guarantee economic long-term profit and survival. While study one examines environmental responses among a stratified sample of UK companies through repeated interviews both in 2006 and 2008, the second study draws on KLD data from S&P500 corporations for the period 1991 to 2006 by distinguishing between changes at firm and at population level. The findings suggest that the state and evolution of corporate environmental strategy are effectively subordinated to contributing towards firms’ fitness, whereby firms mostly attempt to remain profitable and obtain social legitimacy. Even over longer periods of time this behaviour has not changed markedly, except that starting from around 2004 higher levels of oil prices and lower interest rates have spurred more proactive environmental changes among a number of firms. Equally, different motivations, individuals and contextual factors appear to influence the varying patterns of evolution. The thesis fills a gap in the existing literature with respect to the lack of conceptual and empirical contributions about the evolution of corporate environmental strategy by providing new insights into how firms are responding to environmental issues over time and by extending various strands of theory.EThOS - Electronic Theses Online ServiceGBUnited Kingdo