This chapter introduces the concept of Beacon Architecture as a formalized and ordered grouping of architectural elements, describing the constituents, their order, correlation and likely evolution of the grouping; and illustrating its specific value to the public sector. The first half of the chapter builds up to the concept, the reasons behind its specific nature, and its value to enterprises, especially in the public sector. For this, the chapter is split into a number of sections that may be studied separately and that also build up to introduce Beacon Architecture. The sections may be broadly divided as concepts, historical overview, illustrative case studies in public sector transformations along with a summary of peculiar architectural challenges they face, and a cyclical pattern to Architecture Development. After introducing and elucidating on concept and constituents of Beacon Architecture, the chapter delves into its correlation with architecture concepts in currency and its role in mitigating enterprise architecture challenges illustrated earlier in the chapter, before concluding on an assessment of future trends.