NMR standalone analysis, such as Time Domain Analysis, Diffusion Analysis provides an evaluation of the invaded zone because of the shallow depth of investigation of NMR logging measurements. If NMR data are combined with other logs, analysis can furnish even more information about the reservoir. For example, a combination of NMR and deep-resistivity data provides a complete analysis of the fluids in the virgin zone. MRIAN is one of the models that uses this data combination. This chapter contains a complete discussion of MRIAN and its applications. If NMR data are combined with quad-combo data (neutron, density, sonic, and resistivity), then the combination can provide critical information for well completions. For example, when used in a model called StiMRIL, such data can generate information about rock properties, formation lithology, and formation permeability. The StiMRIL model and its application in stimulation optimization are discussed in this chapter.