Wood is a biological material whose properties vary with species, age and growing conditions. Wood strength properties also vary even within a single tree owing to the orthotropic nature of wood. Thus sustainable utilization of wood particularly as a structural material requires prior knowledge of its strength properties. It is not a surprising that in a number of least developed countries such as Uganda, wood selection and utilization is based on the subjective visual grading mechanisms as determined by the visible defects. In addition, the weak quality control systems, loose national timber standards and weak regulatory frameworks prevalent in most developing countries imply that end-users ideally get varying nominal grades. Therefore, this book opens by presenting a review of timber strength characterization approaches and later on focuses on a non-destructive mechanism for predicting timber flexural properties using deflection as a non destructive predictive parameter. The book concludes that the NDE approach can be used to predict the flexural strength quality of structural timber with 95% level of confidence.