The stunning and sudden collapse of global construction behemoth Carillion is tragic, but provides a number of interesting lessons. One, profits are one thing, but the quality of a company’s cash flows are incredibly important. Two, diversification is so critical in investing, whether you are managing an equity portfolio or managing the risk of having most of your net worth tied up in your own company. And finally, as this Bloomberg article highlights, the vast interconnectedness of the global economy, as illustrated by the impact of Carillion’s demise on its vast multitude of creditors and joint ventures.