This paper explores effective IT project evaluation practices in Australia among 36 companies operating in three industry sectors: Finance and Insurance; Mining; and Electricity, Gas and Water Supply. Qualitative analysis of 78 interviews was used to determine characteristics of effective evaluation practices. The study suggests that more formal and sophisticated evaluation methods do not necessarily result in more effective evaluation or better IT project outcomes. Rather, effective IT project evaluation outcomes are more closely related to the drivers of behaviour in organisations such as accountability for results, top-leadership commitment, a strong IT-Business relationship, alignment to strategy, an effective measurement regime, and a willingness to take action. Simplicity and flexibility were also key characteristics underlying effective practices. These conclusions provide both theoretical and practical insights into the evaluation of IT projects in complex environments.