Kinesins are molecular motors that transport intracellular cargo along microtubules in all plant and animal cells. They play key roles in neural development and function, they transport chromosomes during cell division, and they serve as model systems for understanding chemomechanical energy transduction at the level of single protein molecules. We are studying the chemical steps of ATP binding and hydrolysis that underlies the stepping behavior of two-headed motors kinesin-1 and kinesin-2. By attaching 30-nm gold nanoparticles to one head and imaging by dark-field or iSCAT microscopy, we are able to track the dynamics of each head with 2-nm spatial resolution and 1-ms temporal resolution. Because motors take 8 nm steps at ~100 steps/sec, this resolution “breaks the barrier” and enables detection of transient structural intermediates in the motor stepping cycle.