Rotation about the x, y and z axes can be performed in the aligned mode of the program to examine the four degenerate orientations of two modules as shown below-The180° rotations about the axes of the alignment tensor generate multiple solutions for the relative orientations of the two modules. The four different orientations of module 1 relative to module 2 are shown above. The dotted line indicates the covalent junction between the modules. This covalent information may in certain cases be sufficient to select the most probable conformation. The residual dipolar couplings considered here (between spins from covalently bound nuclei) contain purely orientational information; this means that there is complete translational freedom in all Cartesian (x,y,z) directions. Where possible either covalent, experimental or non-bonded interactions can of course be used to place different modules with respect to each other. The program Module will calculate, and localise the steric contacts due to atom-overlap between modules (left).