If Contractors do not effectively implement 4D with BIM, the cost of construction for almost any substantial project – building, infrastructure, industrial – is higher than it needs to be. Money is being wasted, time is being wasted, and sometimes safety is being compromised. BIM enables increasingly more advanced, more intelligent designs. Constructing that design is also increasingly more complex - the congestion of time, material, people, equipment, and space creates unforeseen problems - this is common and continuous. It would seem obvious that many of these problems could be identified and averted if planning was effective. And if these problems were averted then money and time would be saved. But how can planning be effective if a schedule is done “1-dimensionally”, line by line, hundreds of activity connections spanning pages on top of pages? How can a scope of work with say 20 (or more) activities in the same physical area occurring at the same time be well understood? Or how can the safety risk of a crane operating overhead be adequately accounted for when it doesn’t even appear on the schedule? Truth is, no matter how detailed and visually appealing the BIM model, if it doesn’t clearly show the “when” for every activity of construction then how do we know there are not going to be problems, potentially avoidable problems?