As many governments have set the base for Open Data Reuse by facilitating Open data publications, the focus now more and more shifts to the reuse of Open Data and user behaviour. The Government Digital Service (GDS) in the UK launched an API for content from GOV.UK as a step towards making more open data available from government sources and encouraging the reuse. With the launch of the API, the team has begun to use Google Analytics to track hits to the API and its documentation microsite and analyse trends. There is also a feedback facility and any data used is being anonymised. This presents the opportunity to gain insight about user behaviour and evolve the offering of the API. Content has been documented using version three of the OpenAPI specification, which is the proposed open standard for government, and the results will be fed back to the Open Standards team at GDS. The organisation’s tech writing team is developing guidance and will provide training on the documentation. More information and guidance on API standards can be found on the national data portal GOV.UK.