The search for exoplanets, over the last two decades, has been hugely successful. Within the community, there are on going efforts to characterise the large number of exoplanets that have been discovered to date. However, these planets cannot be studied in isolation due to the influence of host stars on both the environment surrounding exoplanets and the exoplanets themselves. Indeed, this necessitates that we characterise the hosts in conjunction with the planets. We now have spectropolarimeteric measurements of around 100 stars that allow us to map their surface magnetic fields and hence model the stellar winds and coronae that together determine the nature of exoplanetary environments.