Control over nano-structure is critical to determining macroscopic properties in a variety of nanomaterials. Bottom-up self-assembly processes are especially desirable to form these structures because they are potentially scaleable. Several groups have demonstrated the use of specific colloidal interactions as a tuning mechanism. In our lab we are now developing simple, reliable and inexpensive methods to drive self-assembly in nanoparticle systems. These approaches are generally based on particle surface modification through the use of small molecules and polymers. With this approach we are able to reliably produce structured aggregates of nanometer dimension at concentrations that make them accessible for use in a variety of applications.