Precise chemical analysis requires accurate assignment of molecular identity. Identification often fails for complex multicomponent samples. I will address this problem by illustrating when, why and how conventional methods for molecular identification can only provide limited sample information. Reliable and high-throughput microscale preparatory multidimensional gas chromatography will be implemented with molecular capture methods. Isolated compounds will be spectroscopically identified to provide absolute structural characterisation. Advanced spectroscopic tools including the synchrotron will provide identification never before possible in gas chromatography. The project will develop improved characterisation for samples of all types.