700 diarrhoeal samples from adult out-patients, 335 from malesrnand 365 from females, were collected from 4 hospitals (TikurrnAnbesa, Zeuditu, Yekatit 12 and Menelik II) and Arada Clinic inrnAddia Abapa. Of the total samples, 394 (56.3%) yielded one orrnmore etiologic agents. Of the positive samples, 191 (57%) werernfrom males and 203 (55.6%) from females. Among 304 singlerninfections, Salmonella was encountered in 13.2%, Shigella inrn13.5%, Entamoeba histolytica in 33.5%, Giardia Lamblia in 28%,rnstrongyloides stercoralis in 7.6% and Trichuris trichiura inrn4.3%. In addition 75 double and 15 triple infections werernfound. No Cryptosporidium were identified in any of thernsamples. Differences in infection status among age groups andrnbetween sex were insignificant (p>O.Ol).rnAmong 45 Salmonella isolates, serogroup C comprised 31.1%,rnB 24.4%, D 13.3%, S.typhi 15.6%, A 8.9% and E 6.7%.rnSusceptibility of Salmonella28.9%, to ampicillin 31.1%,rnisolates to tetracyclineto cephalothin 33.3%,wastorntrimethoprim-sulfamethoxazole 42.2%, to chloramphnicol 53.3%,rnto kanamycin 46.1%, to carbenicillin 62.2%, to gentamicin 91.1%rnand to polymyxin B was 100%. Susceptibility of individualrnserogroups ranged from 0% to ampicillin and tetracycline up torn100% susceptibility to polymyxin B in serogroup A. Of thernSalmonella isolates, 93% were resistant to one or more drugsrnwith a total of 31 distinct resistance patterns (antibiograms).rnFrequently encountered antibiograms were those combinationsrn11hich contained ampicillin, tetracycline, cephalothin,rnkanamycin and trimethoprim-sulfamethoxazole. From 2 to 4 drugrnresistant strains from each serogroups of Salmonella werernselected for plasmid profile analysis. All strains containedrnmultiple plasmids which were larger than 21.2 kilobases (Kb)rnand several others ranging in sizes from 21.2 Kb to 1.8 Kb.rnAmong 50 Shigella isolates, serogroup A comprised 28%, Brn44%, C 18% and 0 10%. Susceptibility of Shigella isolates torntetracycline was 26%, to ampicillin 30%, to cephalothin 36%, torntrimethprim-sulfamethoxazole 48%, to chloramphenicol 50%,rncarbencillin 72%, to kanamycin 80%, to nalidixic acid 86%,rnpolymyxin B 90% and to gentamicin '-las 100%. Among all Shigellarnserogroups, least susceptibility was encountered torntetracycline and ampicillin while greatest susceptibility wasrnobserved to gentamicin, pOlymyxin B and nalidixic acid. Of allrnShigella isolates, 98% were resistant to one or more drugs withrna total of 32 distinct antibiograms. Frequently encounteredrnantibiograms were those combinations which containedrntetracycline, ampicillin, cephalothin and trimethoprimsulfamethoxazole.rnFrom 2 to 6 drug resistant isolates fromrneach serogroups of Shigella, '-Iere selected for plasmid profilernanalysis. As in Salmonella, these also contained multiplernplasmids which were larger than 21.2 Kb and others ranging inrnsizes from 21 Kb to 1.4 Kb.rnThe importance of environmental sanitation, upgrading thernknowledge of personal hygiene among the public and the use ofrnprescribed antibiotics from proper pharmacies duringrnnecessities is recommended. The need for further researchrnespecially on plasmid profile analysis is stressed.