Sir Jeremy Ian Fleming is a British intelligence official who served as the 16th Director of the Government Communications Headquarters (GCHQ), the United Kingdom's signals intelligence, cyber, and security agency, from October 2017 to May 2023. He previously served as Director of the National Cyber Security Centre (NCSC) from 2014 to 2017. Fleming's career at GCHQ began in 1989 after graduating from Pembroke College, Cambridge, with a degree in modern history. He rose through the ranks to lead the agency through a period of heightened global cyber threats, including state-sponsored attacks from nations like Russia and China, the rise of disinformation, and the integration of artificial intelligence in intelligence operations. His tenure focused on strengthening alliances, particularly within the Five Eyes intelligence-sharing network (comprising the UK, US, Canada, Australia, and New Zealand), countering digital espionage, supporting national resilience against cyber incidents, and advocating for ethical frameworks in cybersecurity and AI governance. Fleming was knighted in the 2022 New Year Honours for his services to national security. Since retiring from GCHQ in 2023, he has maintained a low public profile but occasionally speaks at conferences on cybersecurity and global threats, emphasizing the need for vigilance in an increasingly interconnected world. His leadership is remembered for modernizing GCHQ's capabilities amid evolving technological and geopolitical challenges.