Beta-amyloid is a key component of Alzheimer's disease (AD) pathology. Researchers in both academic and industry are actively pursuing the development of imaging tracers and techniques to noninvasively measure local levels of beta-amyloid in the Alzheimer's brain. This presentation summarizes recent data and discusses the opportunities and challenges of imaging plaques containing fibrillar beta-amyloid for the early diagnosis and therapeutic monitoring of amyloid targeted therapies. Further, the value and feasibility of measuring the recently described soluble oligomeric form of beta-amyloid as an alternative noninvasive biomarker is also discussed.