We present 1.6-4.7 $\mu$m images of PPNe and young PNe recently obtained with the Keck Adaptive Optics (AO) system. These observations provide higher angular resolution and probe deeper into the dusty envelopes of post-AGB objects than HST images and, therefore, show with unprecedented detail the morphology of these nebulae. Some objects have limb-brightened lobes displaying a remarkable point-like symmetry, which suggests the presence of underlying precessing jets that may be carving out the nebular lobes. Our images also show a very rich structure at the very small scale of $\sim$0.” 1, including jet-like features, arcs, searchlight beams, as well as faint, extended halos in a number of objects.