Camptothecin (CPT), a monoterpene indole alkaloid, is a promising plant based metabolite known for its anti-tumour activity. CPT is regarded as one of the most promising anticancer drugs of the twenty first century. This compound was isolated through bioassay guided fractionation of various extracts and through chromatographic fractions. Their unique structures were elucidated by nuclear magnetic resonance, mass spectrometry and X-ray analysis. CPT uniquely inhibits an enzyme, topoisomerase I, involved in DNA replication thus inhibiting cell division. CPT and its analogs singly or combined with cisplatin showed efficacy against solid tumors, breast, lung and colorectal cancer, which hitherto have been unaffected by most cancer chemotherapeutic agents.