Hyperpolarization of 13C-labeled substrates can increase their 13C NMR signal by more than 10000-fold, which has allowed magnetic resonance imaging (MRI) of metabolic reactions in vivo. This has already provided a unique insight into the dysregulated metabolic pathways and microenvironment of tumors. Perhaps the best known of the cancer-associated metabolic aberrations is the Warburg effect, which has been imaged in patients using hyperpolarized [1-13C]pyruvate. In clinical oncology there is a requirement to diagnose tumors earlier, better determine their aggressiveness and prognosis, identify novel treatment targets and detect response to treatment earlier. Here we consider some of the hyperpolarized substrates that have been developed and have the potential to meet these requirements and become the precision imaging tools of the future.