“Blockchain and cryptocurrencies are rewriting the global financial landscape”, but who holds the pen? As these technologies surge from niche innovation to mainstream disruption, regulators are standing at a crossroads, i.e., whether to embrace their transformative potential or brace for chaos in an unshackled digital frontier and as these digital assets continue to gain prominence and attention of users & regulators, varied regulatory approaches across countries and regions, creates a complex and often contradictory regulatory environment. While the regulatory landscape poses challenges, it does offer substantial opportunities. Blockchain technology has an untapped potential to revolutionise various sectors, such as banking and finance and supply chain management, inducing transparency, security and efficiency. Similarly, Cryptocurrencies can facilitate financial inclusion by providing unbanked populations with access to financial services, enabling peer-to-peer transactions without the need for middlemen. This chapter examines the regulatory challenges and opportunities that blockchain technology and cryptocurrency bestow in a rapidly evolving financial and investment landscape. It highlights critical challenges, significant hurdles in definitional ambiguities, and technological complexity that regulators face round the world. It even underscores the urgent need to establish common regulatory frameworks, akin to the Basel Accords, to foster cooperation, not individualism. By fostering a common regulatory environment, governments can assert authority to prevent misuse and ensure that benefits are equitably distributed for the greater good, and businesses can harness the technology to pursue innovation in the current realm.