A conjugate of the formula B-L-A, or a pharmaceutically acceptable salt thereof, wherein B is a binding ligand of carbonic anhydrase IX of the formula wherein L is a linker of from 2 to 100 atoms in length and composed of elements including C, N, O and S that covalently attaches B to A; A is a therapeutic agent selected from peptides, oligopeptides, retro-inverso oligopeptides, proteins, protein analogs in which at least one non-peptide linkage replaces a peptide linkage, apoproteins, glycoproteins, enzymes, coenzymes, enzyme inhibitors, amino acids and their derivatives selected from lysine (Lys), asparagine (Asn), threonine (Thr), serine (Ser), isoleucine (lie), methionine (Met), proline (Pro), histidine (His), glutamine (Gln), arginine (Arg), glycine (Gly), aspartic acid (Asp), glutamic acid (Glu), alanine (Ala), valine (Val), phenylalanine (Phe), leucine (Leu), tyrosine (Tyr), cysteine (Cys), tryptophan (Trp), phosphoserine (PSER), sulfo- cysteine, arginosuccinic acid, hydroxyproline, phosphoethanolamine, sarcosine (SARC), taurine, carnosine (CARN), citrulline, anserine, 1,3-methyl- histidine (ME-HIS), alpha-amino-adipic acid, beta-alanine (BALA), ethanolamine, gamma-amino-butyric acid (GABA), beta-amino-isobutyric acid (BAIA), alpha-amino- butyric acid (BABA), L-allo-cystathionine (cystathionine-A; CYSTA-A), L-cystathionine (cystathionine-B; CYSTA-B), cystine, allo-isoleucine (ALLO-ILE), DL-hydroxylysine (hydroxylysine), DL-allo-hydroxylysine (hydroxylysine), ornithine, and homocystine, receptors and other membrane proteins; antigens and antibodies thereto; haptens and antibodies thereto; hormones, lipids, phospholipids, liposomes; cytotoxic agent, such as microtubule inhibitors; antibiotics; analgesics; bronchodilators; beta-blockers; antimicrobial agents; antihypertensive agents; cardiovascular agents including antiarrhythmics, cardiac glycosides, antianginals and vasodilators; central nervous system agents including stimulants, psychotropics, antimanics, and depressants; antiviral agents; antihistamines; cancer drugs including chemotherapeutic agents; tranquilizers; anti-depressants; H-2 antagonists; anticonvulsants; antinauseants; prostaglandins and prostaglandin analogs; muscle relaxants; anti-inflammatory substances; stimulants; decongestants; antiemetics; diuretics; antispasmodics; antiasthmatics; anti-Parkinson agents; expectorants; cough suppressants; mucolytics; and mineral and nutritional additives, or an radio-imaging agent comprising a radioactive isotope of a metal coordinated to a chelating group; and * represents a point of attachment to the rest of the conjugate. wherein L is a linker of from 2 to 100 atoms in length and composed of elements including C, N, O and S that covalently attaches B to A; A is a therapeutic agent selected from peptides, oligopeptides, retro-inverso oligopeptides, proteins, protein analogs in which at least one non-peptide linkage replaces a peptide linkage, apoproteins, glycoproteins, enzymes, coenzymes, enzyme inhibitors, amino acids and their derivatives selected from lysine (Lys), asparagine (Asn), threonine (Thr), serine (Ser), isoleucine (lie), methionine (Met), proline (Pro), histidine (His), glutamine (Gln), arginine (Arg), glycine (Gly), aspartic acid (Asp), glutamic acid (Glu), alanine (Ala), valine (Val), phenylalanine (Phe), leucine (Leu), tyrosine (Tyr), cysteine (Cys), tryptophan (Trp), phosphoserine (PSER), sulfo- cysteine, arginosuccinic acid, hydroxyproline, phosphoethanolamine, sarcosine (SARC), taurine, carnosine (CARN), citrulline, anserine, 1,3-methyl- histidine (ME-HIS), alpha-amino-adipic acid, beta-alanine (BALA), ethanolamine, gamma-amino-butyric acid (GABA), beta-amino-isobutyric acid (BAIA), alpha-amino- butyric acid (BABA), L-allo-cystathionine (cystathionine-A; CYSTA-A), L-cystathionine (cystathionine-B; CYSTA-B), cystine, allo-isoleucine (ALLO-ILE), DL-hydroxylysine (hydroxylysine), DL-allo-hydroxylysine (hydroxylysine), ornithine, and homocystine, receptors and other membrane proteins; antigens and antibodies thereto; haptens and antibodies thereto; hormones, lipids, phospholipids, liposomes; cytotoxic agent, such as microtubule inhibitors; antibiotics; analgesics; bronchodilators; beta-blockers; antimicrobial agents; antihypertensive agents; cardiovascular agents including antiarrhythmics, cardiac glycosides, antianginals and vasodilators; central nervous system agents including stimulants, psychotropics, antimanics, and depressants; antiviral agents; antihistamines; cancer drugs including chemotherapeutic agents; tranquilizers; anti-depressants; H-2 antagonists; anticonvulsants; antinauseants; prostaglandins and prostaglandin analogs; muscle relaxants; anti-inflammatory substances; stimulants; decongestants; antiemetics; diuretics; antispasmodics; antiasthmatics; anti-Parkinson agents; expectorants; cough suppressants; mucolytics; and mineral and nutritional additives, or an radio-imaging agent comprising a radioactive isotope of a metal coordinated to a chelating group; and * represents a point of attachment to the rest of the conjugate.