There is significant potential for the use of nanoparticles in cementitious materials, especially in ultra-high performance concrete. These nanoparticles can further increase packing density, accelerate the pozzolanic reaction or can be used to induce new properties to the material, such as air purification or self-cleaning. Little is known about the interaction mechanisms between nanoparticles in cementitious materials, including their dispersion quality. The characterization of these nanoparticles can be challenging, especially when these nanoparticles interact with cementitious materials and their reaction products during hydration. Thorough characterization of the nanoparticle system is essential to understand how to optimize mixing constituents, procedures, and parameters. This study explores the feasibility and potential use of several characterization methods for investigating colloidal nanosilica in a concrete environment. These techniques include dynamic light scattering, zeta potential, atomic force microscopy, scanning electron microscopy, cryogenic SEM, and focused ion beam microscopy. These methods allow for characterization of nanoparticles, nanoparticles interacting with pore solution that represents a concrete environment, nanoparticles interacting with polymers used as superplasticizers, and nanoparticles interacting with a cementitious material. These tools allow for studies on the nano-length scale at short times to observe and measure parameters such as particle size distribution, polydispersity index, and zeta potential.