The problem of polypharmacy is complex, pervasive, and expanding. Appropriate prescribing of antihypertensive therapy for older people might help reduce medication burden, but it begins with a better understanding of what the evidence offers and where the evidence is quiet.In the first of this three-part series on antihypertensive medications for older people, we will trace the history of treating blood pressure with medication, from the expert opinion opposing treatment, to the observational data that led to paradigm shifts. We will follow the trail of evidence to randomized controlled trials (RCT) demonstrating the clear benefit of better control of blood pressure for all adults, regardless of age.RCT first evaluated any treatment against placebo, then began comparing one medication with another, and finally, more intensive control compared with less intensive control. Eventually professional societies bundled the evidence into guidelines to help busy prescribers and pharmacists wisely advise the consumers at the coal-face.In this first part of this series, we will present the evidence that favors intensive therapy in older people, that lower is better. In the second part, we will present evidence that highlights the dangers of going too low, and that stopping blood pressure-lowering medication might help. In the third part, we will discuss the evidence, new and old, that shows what happens when you stop.