High-impact practices, such as learning communities, capstones, undergraduate research, and community-based experiences, are effective pedagogies. Most of these practices have been around for decades. By clustering the effective elements of these activities through the term "high-impact practices," we bring together elements which we know are effective pedagogies, without weight to any one practice over another. The vast majority of campuses can proudly point to multiple high-impact practices happening somewhere within their institutions, not just one or two. Thus, to talk singularly about high-impact practices--and the assessment of them--would be like evaluating just one tire on a car. To ultimately understand what makes an institution move requires looking at all of the moving parts. And given the intense focus across institutions of higher education on identifying, tagging, and touting their high-impact practices, assessment is what will separate the committed practitioners from the casual adopters. A good assessment plan for high-impact practices starts with acknowledging three things. One, the name alone does not make them high-impact. Two, evidence of effect requires assessing more than outcomes, alone. And three, assessment must be, at every stage, attentive to equity. Building upon these three ideas, this Occasional Paper outlines a process of effectively assessing high-impact practices at your institution.