This award supports a group activity involving ultracold science and high-resolution laser spectroscopy. The areas to be explored involve 1) ultracold collisions and reactions of Rb2, with effort devoted to efficient production in traps and BEC's; 2) ultracold heteronuclear KRb molecules and their interactions, with an emphasis on dipolar effects; 3) ultracold Rydberg-Rydberg interactions and the resulting molecular states; and 4) precision spectroscopy, primarily of fundamental systems such as H2 and Fe II. The group grant encourages the investigators to tackle technically complex experiments that require significant shared resources and a high degree of cooperation between the participants. The broader impacts involve the education of graduate students as well as possible applications in areas such as chemistry, plasma science, quantum computing, nanoscience, antimatter and cosmology.