The 3DDLS spectrometer has been introduced by LS Instruments. It employs a 3-D cross-correlation technique to suppress the multiply scattered light present at measurements with turbid samples. The method is an extension of the technique of dynamic light scattering, performing two experiments simultaneously. The spectrometer offers easy alignment and a compact, rugged design. It characterizes sample properties such as molar mass, interaction effects, particle size distribution, stability of colloidal products, and particle form and structure factors.