If you get a cancer diagnosis you need to actively engage in your treatment, or else bad things can happen. Putting all your trust in the medical system—or avoiding the medical system—might have worked for you in the past, but it can be fatal with cancer. With a cancer diagnosis, it’s increasingly important that you understand the unique testing and treatments that are exploding and available to you, to participate in choosing the best treatment options for you, and to maximize the positive impact of behaviors only you control, such as diet, exercise, rest, attitude, and adherence to doctor’s orders. You cannot make informed, educated decisions about your care or navigate your care treatment, unless you actively participate. For example, your doctor may recommend an invasive treatment like surgery or chemotherapy, which are standard, when you have other, less invasive options, but are more experimental. You need to personalize your treatment by gathering diagnostic data and identifying targeted treatments unique to you, advocate for access to the latest care options, and learn about and follow guidelines for a healthy lifestyle.