The assessment of peptide bioactivity and potency by probing topographic three-dimensional space can be explored through allosteric modulation of disulfide bridges.1,2 Recent development of carbon based isosteres for disulfide motifs has shown that restricted conformation can lead to increased biopotency.3 Here, we describe the development of synthetically simpler organometallic cystine analogues. Through stable chelation of the metals (e.g. M = Cu, Lu, Ga, Hg etc.), via sequence incorporated residues, predictable geometries and enhanced biological potency and selectivity can be achieved. Stable incorporation of metal ions also allows for radiolabelling of highly stable, target selective, and water-soluble peptide precursors for generation of carrier-free targeted radiopharmaceuticals.4 Several examples from diverse therapeutic families will be discussed. The generation of these organometallic peptide analogues provide insights into allosteric modulation and the roles disulfide bridges play in native peptide conformation in addition to creating opportunity for new therapeutic applications.