Weakly bonded guest species can, in some structural situations, easily desorb from the solid supramolecular compounds. An excellent illustration may be organic zeolites having an open system of interconnected cavities and channels. If filled with volatile guest the system may be extremely unstable out of its equilibrium conditions. Characterization of such systems presents specific problems because it is quite common that decomposition (desorption) is not always easily observed and the product after guest desorption may have appearance of a well stoichiometric and stable compound. Thus, it is a standard duty of supramolecular chemists to verify if the sample used for an analytical procedure is identical to the one which was the product of supramolecular synthesis. The present paper will concentrate on four experimental methods which can conveniently be used for analytical and structural characterization of supramolecular compounds either in situ or at conditions which guarantee reliability of the results. These are: x-ray diffraction, calorimetry, gravimetry with the use of levitating sample holder and special version of thermogravimetry. X-ray diffraction is, perhaps, the most obvious method of choice since, if the crystalline sample is used without drying (with some excess of mother liquor) diffraction data coming from the crystalline component of the sample is only slightly disturbed by the presence of amorphous material. Examples will be given how sensitive the crystals can be to exposition to open air or nonequilibrium temperature of the compound. Calorimetry has its great advantage of measuring change of thermodynamic functions when going to an equilibrium. With appropriate choice of experimental setup one may obtain information both on enthalpies and kinetic course of the formation of supramolecular complexes. Equilibria can be measured also with the use of levitating sample holder and varying external thermodynamic and chemical conditions. Sorption or desorption is then followed by weight balance and, in some situations may be compared to x-ray powder patterns taken at comparable conditions. A modification of thermogravimetry may be used in order to determine the quantitative composition of labile compounds. It consists of two stages, the first is an isothermal guest desorption which is then followed by classic thermal decomposition. The paper will illustrate specific problems of each of the above mentioned experimental techniques, when applied to study labile complexes.