Precision medicine aims to tailor treatments to individual patients rather than using one-size-fits-all approaches. Current clinical trials often fail to account for individual variability, leading to ineffective or harmful treatments for many. Nicholas J. Schork argues that N-of-1 trials, which focus on individual responses, are essential for precision medicine. These trials involve testing interventions on a single person, often by cycling through different treatments and comparing their effects. While N-of-1 trials are not always feasible, they offer a way to better understand how individuals respond to treatments, especially for rare diseases and conditions where standard trials are not effective. N-of-1 trials can be formalized and scaled up, but they require addressing practical challenges such as the diversity of health-monitoring devices, the development of new ones, and the identification of appropriate biomarkers. A cultural shift is also needed in regulatory agencies, pharmaceutical companies, and clinical settings. Despite these challenges, there is growing interest in precision medicine, driven by advances in genomics, the availability of cost-effective health-monitoring devices, and increased support for patient-centered research. N-of-1 trials could help reduce the costs of inappropriate treatments and improve outcomes for patients with chronic or complex conditions. They could also be useful in the early stages of drug development, repurposing drugs, and determining safe dosages. However, there are significant barriers to widespread adoption, including regulatory concerns, the high cost of personalized treatments, and the need for more effective biomarkers and data-analysis methods. Nonetheless, the shift towards precision medicine is gaining momentum, with governments and funding bodies increasingly supporting patient-centered approaches. Ultimately, the goal is to transform everyday clinical care into solid N-of-1 trials, ensuring that treatments are tailored to individual needs.Precision medicine aims to tailor treatments to individual patients rather than using one-size-fits-all approaches. Current clinical trials often fail to account for individual variability, leading to ineffective or harmful treatments for many. Nicholas J. Schork argues that N-of-1 trials, which focus on individual responses, are essential for precision medicine. These trials involve testing interventions on a single person, often by cycling through different treatments and comparing their effects. While N-of-1 trials are not always feasible, they offer a way to better understand how individuals respond to treatments, especially for rare diseases and conditions where standard trials are not effective. N-of-1 trials can be formalized and scaled up, but they require addressing practical challenges such as the diversity of health-monitoring devices, the development of new ones, and the identification of appropriate biomarkers. A cultural shift is also needed in regulatory agencies, pharmaceutical companies, and clinical settings. Despite these challenges, there is growing interest in precision medicine, driven by advances in genomics, the availability of cost-effective health-monitoring devices, and increased support for patient-centered research. N-of-1 trials could help reduce the costs of inappropriate treatments and improve outcomes for patients with chronic or complex conditions. They could also be useful in the early stages of drug development, repurposing drugs, and determining safe dosages. However, there are significant barriers to widespread adoption, including regulatory concerns, the high cost of personalized treatments, and the need for more effective biomarkers and data-analysis methods. Nonetheless, the shift towards precision medicine is gaining momentum, with governments and funding bodies increasingly supporting patient-centered approaches. Ultimately, the goal is to transform everyday clinical care into solid N-of-1 trials, ensuring that treatments are tailored to individual needs.