The exercise of prosecutorial discretion is a unique executive act that continues to be very well-protected from public scrutiny in many jurisdictions throughout the world. In this article, I attempt to survey virtually the entire body of case law on the limits of prosecutorial discretion in Singapore. Probably because prosecutorial discretion is protected by the Constitution, it took a while for the Singapore courts to retreat from its initial characterisation of the discretion as absolute and outside the scope of any form of review. Against a wider backdrop of increasing rights-consciousness (especially within the courts) and the public demand for transparency and accountability, the legal position has evolved to its current and more legally defensible form, viz, prosecutorial discretion is not absolute, and can be subject to, inter alia, constitutional challenge. It may well be a while before this position evolves again, but the natural progression from this, as seen in other jurisdictions, is the public release of general guidelines for prosecution. While such a progression brings about certain benefits, it is not without its challenges and may be motivated (though not exclusively) by extra-legal considerations such as politics and populism. Ultimately, only the state and its people can decide on the conception of the rule of law that it subscribes to, and it is with humble hope that this article may be used as a reference point when future issues pertaining to prosecutorial discretion are considered.