Coherent electronic interactions in semiconductor nanostructures are investigated by two-dimensional Fourier-transform (2DFT) spectroscopy. Based on and superseding transient four-wave mixing techniques, 2DFT spectroscopy is the optical analogue of multidimensional nuclear magnetic resonance spectroscopy. This new technique is used to revisit exciton and continuum dynamics, such as classical and quantum-mechanical coupling and many-body interactions. Recent results and varying 2DFT projections separate quantum-pathways, which can be expressed by differing double-sided Feynman diagrams. Moreover new apparatus allows for better control of the phase between the numerous pump-beams, enabling further refinement of the coherent interactions.