The 2015 Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel (aka Nobel Prize in Economics) has been awarded to Angus Deaton. I won't write too much here, but if you want to know a good deal about Deaton and his work see the links in this post by Tyler Cowen, this one by Alex Tabarrok, and additional links here.
Chris Blattman has an excellent piece, which I will largely echo. My own intersection with Deaton's work was during my PhD, where I undertook a fairly large (~680 households) household survey in Northeast Thailand. The Analysis of Household Surveys was one of many guidebooks that helped greatly with setting up the survey (along with several World Bank publications on the survey methods for the Living Standards Measurement Surveys which Deaton was also involved in), and the book was invaluable in the analysis phase (as you would expect from the title). In reading Deaton's work, I have come to realise just how much of his thinking had already been indirectly a part of my development economics training, even if my lecturers were not always explicit about their sources.
As others have mentioned, this is a very well deserved award for a wide body of work that has greatly enhanced our understanding of poverty, inequality, consumption, and development economics more generally. His contributions span both the theoretical, the empirical, and the analytical. Deaton's name had no doubt been on the shortlist for a number of years.