To lead is one thing, but to lead effectively is a totally different matter. Leadership theories and studies prominently address leadership as a style or sometimes as activity tied to specific region or race. However, developing a set of positive and negative behaviours that leaders can learn and practice wherever they go is what this book set to provide. When talking about behaviours, we talk here about perceived behaviours, not actual ones. This creates a link between leaders and followers who judge leaders’ behaviours on the ground. We start the chapter with the journey of developing the behavioural taxonomy by presenting the efforts of Professor Robert Hamlin and colleagues in this field and illustrate Hamlin’s Model for Leadership Effectiveness and Ineffectiveness. As this is a recently developed model, we take some time to elaborate the developmental aspects of it and how it started to gain attention by management scholars. Implementing Hamlin’s Model in areas other than the West, such as Middle East, is yet another success factor we refer to in this chapter.