Defective synthesis of hemoglobin gives rise to a group of hereditary disorders. If the defect arises from a genetic mutation producing abnormal protein chains, the condition is classified as hemoglobin variant. Whereas, if the structure is normal but the synthesis is reduced, they are denominated as thalassaemia. This article aims to describe the laboratory diagnostic approach in four cases of hemoglobin disorders in order to illustrate the role of laboratories and discuss the role of clinical pathologists as a link between physicians and laboratories in diagnostic clarification.473271278Ayala, S., Colomer, D., Pujades, A., Aymerich, M., Vives Corrons, J.Ll., Haemoglobin Lleida: A new α2-globin variant (12 bp deletion) with mild thalassaemic phenotype (1996) British Journal of Haematology, 94 (4), pp. 639-644Beard, M.E.J., Potter, H.C., Spearing, R.L., Brennan, S.O., Haemoglobin Pierre-Benite - A high affinity variant associated with relative polycythaemia (2001) Clinical and Laboratory Haematology, 23 (6), pp. 407-409. , DOI 10.1046/j.1365-2257.2001.00350.xBissé, E., Schaeffer, C., Haemoglobin Noah Mehmet Oeztuerk (alpha(2) delta(2)143 (h21)his→tyr. A novel delta-chain variant in the 2,3-dpg binding site (2008) J Chromatogr B Analyt Technol Biomed Life Sci, 871 (1), pp. 55-59Burtis, C.A., Ashwood, E.R., (2006) Tietz Textbook of Clinical Chemistry and Molecular Diagnostics, , Elsevier SaundersClark, B.E., Thein, S.L., Molecular diagnosis of haemoglobin disorders (2004) Clinical and Laboratory Haematology, 26 (3), pp. 159-176. , DOI 10.1111/j.1365-2257.2004.00607.xClarke, G.M., Higgins, T.N., Laboratory investigation of hemoglobinopathies and thalassemias: Review and update (2000) Clinical Chemistry, 46, pp. 1284-1290. , 8 IIColah, R.B., Surve, R., Sawant, P., D'Souza, E., Italia, K., Phanasgaonkar, S., Nadkarni, A.H., Gorakshakar, A.C., HPLC studies in hemoglobinopathies (2007) Indian Journal of Pediatrics, 74 (7), pp. 657-662. , DOI 10.1007/s12098-007-0117-8De Rosa, M.C., Alinovi, C.C., Schinina, M.E., Clementi, M.E., Amato, A., Cappabianca, M.P., Pezzotti, M., Giardina, B., Hb Santa Clara (β97His → Asn), a human haemoglobin variant: Functional characterization and structure modelling (2007) Biochimica et Biophysica Acta - Proteins and Proteomics, 1774 (10), pp. 1299-1306. , DOI 10.1016/j.bbapap.2007.08.004, PII S1570963907001884England, J.M., Frase, P.M., Differentiation of iron deficiency from thalassaemia trait by routine bloodcount (1973) Lancet, 1, pp. 449-452Greer, J.P., Foerster, J., (2008) Wintrobe's Clinical Hematology, , Lippincott Williams & WilkinsKohne, E., Kleihauer, E., Hemoglobinopathies: A longitudinal study over four decades (2010) Dtsch Arztebl Int, 107 (5), pp. 65-71Lewis, S.M., Bain, B.J., Hematologia prática de Dacie e Lewis (2006) ArtmedMcPherson, R.A., Pincus, M.R., (2007) Henry's Clinical Diagnosis and Management by Laboratory Methods, , Elsevier SaundersSchechter, A.N., Hemoglobin research and the origins of molecular medicine (2008) Blood, 112 (10), pp. 3927-338Storti-Melo, L.M., Mangonaro, P.H., Three-dimensional visualization of human hemoglobin phenotypes with HPLC (2009) Genet Mol Res, 8 (1), pp. 354-363Trent, R.J.A., Diagnosis of the haemoglobinopathies (2006) Clin Biochem Rev, 27 (1), pp. 27-38Yates, A.M., Mortier, N.A., The diagnostic dilemma of congenital unstable hemoglobinopathies (2010) Pediatr Blood Cancer, 55, pp. 1393-1395Zanella-Cleon, I., Joly, P., Phenotype determination of hemoglobinopathies by mass spectrometry (2009) Clin Biochem, 42, pp. 1807-1817