The energy transition and the rapidly changing climate require unparalleled efforts and solutions. Various legal instruments can provide institutional guidance in this unfamiliar territory and build an ecological framework in a modern constitution. This chapter outlines constitutional structures for ten key environmental elements at all levels of constitutional architecture. These include the preamble, the institutional constitution (encompassing and binding all three branches of government), the fundamental rights section, specific guiding provisions requiring the state to value and preserve nature, rights safeguarding nature itself, rights to access environmental information, independent oversight mechanisms, provisions enabling litigation in defence of nature, state of emergency clauses adapted to ecological threats, and immutable components of the amendment clause. Together, these components form a modular constitutional framework that can be adopted individually or collectively to better prepare a country for constitutional decision-making in light of the inevitable changes that lie ahead.