In laser-induced inertial confinement fusion the understanding of the physical process taking place in the plasma atmosphere surrounding the target is extremely important because it is here where the energy is absorbed and transported to the core region. Optical probing of the target atmosphere can provide information about this important region by using laser diagnostics such as interferometry, Faraday rotation, and Thomson scattering. Interferometry is used to determine electron density distributions in the plasma and has permitted the direct observation of effects due to ponderomotive forces in the plasma. Thomson scattering is another diagnostic which can help understand some of the interaction process taking place in plasma corona. This technique, apart from providing electron and ion temperature inside the plasma, can provide direct information about wave-wave decay process, ion turbulence, and other collective effects. It has been successfully used to isolate some nonlinear wave phenomenon in 10.6 um laser-produced plasmas.