Several molecular junction types have been studied in silico so as to identify the key descriptors connecting molecular structure with the junction conductance and develop more conductive systems. 1) For thiophene-based wires with tunable charge carrier type, we have analyzed the molecular orbital factors affecting their conductance and devised a simple in silico tool for predicting the carrier type change based on the charge transfer trends. 2) In the context of through-space transport, we have investigated diverse π-stacked dimers, pertinent both to molecular junctions and semiconductors. We have illustrated that the same chemical concepts define their performance in these two very different types of electronic assemblies. These concepts were employed to design more conductive junctions. 3) Moving beyond conventional π-conjugated systems, we have studied molecular junctions featuring fully saturated hydrocarbons. For various carbon nanothreads, we have illustrated that their conductance is driven by their complex topology. The latter was utilized to develop new multidimensional nanothreads with unprecedented for systems lacking π-conjugation zero-bias transmission probabilities. We have also demonstrated that hydrocarbons with various σ-aromaticity patterns display diverse conductance behavior, particularly outstanding in the case of σ-antiaromatic cores. These results have been reported in high-impact peer-reviewed journals (e.g. Journal of Physical Chemistry Letters, Journal of the American Chemical Society, etc.), cited by other scientists, reported to diverse audiences via scientific meetings (including oral presentations at the International Workshop on “Molecular-Scale Electronics: Concepts, Contacts, and Stability” in UK in 2017, ValBO ICQC satellite meeting on Understanding Chemistry and Biochemistry with Conceptual Models in France, 54th Symposium on Theoretical Chemistry “Non-Covalent Interactions” in Germany and 9th International Conference on Molecular Electronics in France in 2018) and outreach activities (e.g. the MSCA Falling Walls Lab and the Lindau Nobel Meeting in 2017).