A recent LOQ experiment revealed that co-monomers are homogenously distributed within regions of colloidal poly(NIPAM) microgel particles. This proposal has two aims: (1) refine the previous results using the larger Q range available in SANS2D to obtain data for entire particles; (2) probe how hydrophobic co-monomer incorporation influences how aqueous poly(NIPAM)-based microgels interact with non-polar co-solvents (e.g. ethanol, hexanol, decanol) to assess their suitability for applications requiring affinity for hydrophobic materials (e.g. oil removal from water). Systematic use of deuterated NIPAM/co-monomers/co-solvents will permit contrast matching to study component local distribution. Understanding how co-monomer distribution and particle/co-solvent interactions relate to co-monomer nature/particle properties will aid development of microgels tuned to ¿hydrophobic¿ applications.