Two-dimensional suspensions are interesting both for a fundamental study of suspension dynamics and mechanics, as well as for the applications in the stabililization of high interface systems such as foams and emulsions. Control over the suspension structure of a planar particle monolayer can be achieved by destabilizing an initially crystalline monolayer of colloidal particles. This requires adequate combinations of salt and surfactant in order to tailor the interaction potential. A magnetic rod interfacial stress rheometer is used to characterize the dynamic rheological behaviour of particle monolayers with a controlled aggregate structure. The linear viscoelastic properties and some non-linear rheological features will be shown. Also the compressional rheology is characterised using a Langmuir trough. It will be shown that interfaces with both high elastic shear and compressional moduli can be obtained. As all microstructural information can be readily accessed, direct comparison between structural and mechanical properties is possible, providing mechanistic insight in the yielding and flow behaviour of these systems. The role of controlled surface rheology in emulsion and foam formulation will be briefly addressed.