If you heard about the blast in Congo, here's something to consider. High density, unconstrained growth in developing countries can have disastrous consequences when citizens are packed in near hazardous sites. In this case, an arms depot that was in empty space a few years ago is now surrounded by poor quality, high density housing.
This article offers a more indepth perspective on the need for urban design in the developing world. Interesting read.
It's the responsibility of governments to not only build sustainably and efficiently, but also to avoid placing citizens in harm's way. It's the responsibility of service providers, vendors, and those who support governments to educate them about the tools that can help!