The PI plans to observe the magnetic field and rotation properties of low mass stars throughout their pre-main sequence phase. He will make use of the Zeeman Effect as seen in high-resolution optical spectra of young stars obtained with the NASA?s IRTF CSHELL and McDonald Observatory IGRINS spectrometers. The Zeeman Effect refers to the splitting of spectral lines that is observed in the presence of a magnetic field. The goal of this work is to test dynamo models of young stars, which has broader impacts to understanding the solar dynamo, extrasolar planet-star interactions. This project will also train a graduate student in research techniques.