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Abstract Magnetic resonance imaging (MRI) is a powerful and widely used in vivo imaging technique that enables whole body imaging without ionizing radiation. In clinical practice,¹H MRI is employed for imaging anatomical and physiological states via monitoring of protons in water and lipids. In order to monitor biochemical processes at the molecular level, several research groups are exploring responsive MRI agents that alter their signal upon interaction with an analyte or biological environment of interest. Fluorine (¹⁹F) MRI agents are promising due to the¹⁹F nucleus having similar magnetic resonance (MR) properties to proton and the absence of endogenous¹⁹F in living systems, resulting in no background signal. In order to make responsive¹⁹F MR agents for molecular imaging and analysis, fluorinated platforms must be developed in which their¹⁹F MR signal changes after interacting with a target analyte. A promising strategy is to use paramagnetic metals to modulate the¹⁹F MR signal by altering the relaxation rates and/or chemical shift of an appended¹⁹F imaging tag. In this concept, we provide an overview of the theoretical principles and molecular design strategies that have been exploited in the design of responsive¹⁹F MR agents, with a specific focus on agents based on small molecule paramagnetic metal ion chelates.