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Background: Acinetobacter species cause hospital outbreaks and are often multidrug resistant. A wide range of resistance determinants make them successful nosocomial pathogens. In the present study, authors have identified and speciated Acinetobacter from various clinical specimens by a simplified phenotypic identification scheme determined their antibiotic susceptibility pattern focussing on Carbapenem resistance and have also evaluated their biofilm producing ability. Method: Clinical samples were screened for Acinetobacter species and isolates were speciated. Antibiogram was determined by performing Kirby-Bauer disc diffusion method. Isolates resistant to Carbapenems were subjected to Modified Hodge Test (MHT) and Meropenem-EDTA Combined Disc Test (CDT). These isolates were further evaluated for their biofilm forming ability by the Microtitre Plate Method. Results: Out of 174 isolates, the species most frequently isolated was Acinetobacter calcoaceticus-baumannii complex (ACB) (89.1%). 70.1% isolates were resistant to Carbapenems, of which 45.1% were MHT positive and 73.8% were CDT positive. 63.7% of the isolates were biofilm producers. Conclusion: Simple identification schemes and antimicrobial susceptibility testing are cost effective and require fewer resources. Screening for Carbapenem resistance can help avoid unnecessary use of broad-spectrum antibiotics and thereby prevent treatment failure. Biofilms lead to decreased penetrability of antibiotics and make managing infections a clinical challenge. Further research is required to have a better understanding of the mechanism of biofilm formation and its implication in drug resistance. Duration and type of study:This was a prospective study done on clinical samples like pus, urine, blood, respiratory specimen, peritoneal fluid, cerebrospinal fluid received for culture and sensitivity in the department of Microbiology at M.S Ramaiah Medical College and Teaching Hospital during the period of 1 year (January 2016 to December 2016).Sampling method: All the samples sent for culture and sensitivity to the microbiology laboratory over the period of one year were included in the study. Sample size calculation:Sample size calculation was based on a previous study conducted by Mindolli et al [2] where Acinetobacter species were isolated from 4.25% of positive cultures. In the present study, considering an absolute precision of 3% and confidence level of 95%, sample size was calculated to be 174 with the help of n-master software. Inclusion criteria:Clinical samples like urine, pus, respiratory specimen, peritoneal fluid, blood, cerebrospinal fluid were screened for Acinetobacter species in a period of 1 year ( Exclusion criteria: No exclusion criteria envisaged.Data analysis: IBM SPSS version 20 software was used for analysing the data. Ethical consideration and permission:Ethical clearance was obtained from the institutional ethical committee.Laboratory procedures-All specimens received were subjected to direct microscopy and culture: The specimens were inoculated ...