The unsustainability of fossil fuels and concerns for the environment have led to aconsiderable increase in demand and support for renewable energy technologiesover the last two decades. The UK, with a natural abundance of wave and tidalresources, is at the forefront of marine technology development but, compared tomore conventional fuels, the marine energy sector still remains in its infancy. Thiswork uses a Technological Innovation Systems (TIS) approach to assess andevaluate how technological and institution changes affected the evolution of theUK's marine energy sector between 2000 to present and providesrecommendations on how best to accelerate the development of marine energytechnology.The TIS approach facilitates the analysis of a system which aims to grow anddevelop a specific emerging technology by establishing the extent to which eventsor activities, which occurred within the UK's marine energy sector, contribute tothe fulfilment of seven 'system functions'. The events are defined, classified andmapped by applying a historical event analysis to marine energy in the UKbetween 2000 and 2015. The interactions and interdependence between thesystem functions provided insights into which functional requirements needed tobe fulfilled in order for the marine energy system to be successful.The analysis showed that as marine energy technology developed, complexfunctional interactions formed between the different phases of technologicaldevelopment. Knowledge development and knowledge diffusion (through keyevents, such as the opening of the European Marine Energy Centre in 2003) wereidentified as the system functions responsible for pushing marine technology fromthe research phase (2000-2005) to the demonstration phase (2005-2010).Consistent and significant entrepreneurial activities throughout the demonstrationphase, together with mounting lobby activities and increased market attraction(through the introduction of bands to the Renewable Obligations scheme by theGovernment in 2009) drove marine technology through to the pre-commercialphase (2010-2015). Here, significant positive activity across all system functions inthe sector was initially seen but negative fulfilment of the market formationfunction (through the Electricity Market Reforms, announced by Government in2011) and the departure of several key actors (withdrawal of Siemens and thecollapse of Pelamis Wave Power) led to increased risk and uncertainty amongstinvestors and a reduction in entrepreneurial activities.Whilst marine technology in the UK has made significant ground towardscommercialization over the last decade, the results from this study demonstratethat better fulfilment of the guidance of the search and market formation functionsis required to help support and stimulate the formation of marine energy marketsand reduce risk and uncertainty for investors. This, in the form of clear, long term,consistent and timely policy guidance from the Government, together with morestreamlined and efficient funding mechanisms will help drive the sector towardscommercialization.