Bacteria have evolved to sense changes in their environment and move to change their position in order to avoid unfavourable conditions or manoeuvre towards new niches using chemotaxis signal transduction pathway. Bacterial chemosensors respond to external stimuli with unique precision and sensitivity - a key survival trait in search for nutrients and locating a target host cell, and as such, are considered to be critical for bacterial colonisation and pathogenicity The well-researched E. coli chemotaxis system pathway (receptor-CheA/CheW-CheY-flagella) has previously served as a reference for the characterisation of chemotaxis in other bacteria. In recent years, however, our knowledge of chemotaxis pathways has progressed from a simple E. coli paradigm to a much more complex scenarios in other bacteria where similar, but more complex pathways exist. Gastrointestinal pathogen Campylobacter jejuni encodes a single chemosensory pathway relaying signal through eleven sensory receptors, seven of which sense external ligands. It also encodes other proteins involved in the chemotaxis signalling pathway that are not found in E. coli, but common in other microbes. For example: CheV, a two-domain protein consisting of fused CheW and CheY-like domains. Similarly, C. jejuni CheA is also a two-domain protein combining a catalytic HK and a regulatory RR domains, unlike the CheA in E. coli. The functions of these proteins are yet to be elucidated in C. jejuni or other bacteria. Furthermore, identification of specific chemoreceptor-ligand interactions has been problematic and C. jejuni is the only organism, other than E. coli, where specific ligands for 6 of the 7 existing external sensory receptors have been definitively identified. Notably, we have now characterised five of the seven C. jejuni external sensors, including the aspartate chemosensory receptor CcaA and the multi-ligand receptor CcmL, capable of responding to 5 repellents and 5 attractants. Additionally we have elucidated signalling pathway partners, particularly CheV and CheW, for each of these sensory receptors.