Biochar is a promising approach in environmental remediation, CO2–capture, and soil improvement. This chapter provides a comprehensive overview of the recent progresses in this domain and novel integrations among three main aspects: (i) latest biochar synthesis approaches such as fast pyrolysis and hydrothermal carbonization; (ii) emerging functionalization strategies for transforming biochar, namely mineral-doped biochar, nanobiochar, and composite based of biochar; (iii) novel, interdisciplinary applications including precision agriculture, water purification engineering advances in multiple types of systems. By the integration of three pillars, this intermediate way surmounts the blanks in today’s literature due to emerging a single or other technically relevant as well real-world relevant point of views, and broadens their spectre on a complete starting point and further development for biochar usage toward sustainable societies. This chapter also includes environmental and scalability toward advanced biochar systems, including nanoparticle toxicity and their energy content of production. It also touches on the financial feasibility and regulation fallout from widespread implementation. The chapter is unique compared to the available literature in that it “connects” to state-of-the-art room scale developments for the targeted end-use applications. It places biochar as a soil amendment and multi-service, climate adjusted circular economy enabler technology. This is intended to guide future research and policy, as well as industry innovation in the sustainable and responsible development of biochar technologies.