This document discusses methods and conceptual considerations for content design and user interface architecture for multiscreen projects according to the building block principle. It introduces concepts like multiscreen strategies, content modeling, content structure mapping, content and UI mapping, and using a building block approach to define smallest reusable elements that can be combined to create interfaces for different devices and contexts. The document is from a presentation given at the World Usability Day at Hochschule Aalen on November 9th, 2017.