Background: Acinetobacter species are a key source of hospital acquired infection in debilitated patients. Acinetobacter baumannii being the commonest species implicated in such infections. The clinical significance of Acinetobacter genus is partially due to its capability to develop resistance against broad spectrum antibiotics including beta lactams, cephalosporins, aminoglycosides and quinolones. Resistance to carbapenems is also on the rise. The objective of this study was to evaluate in vitro antimicrobial activity of Tigecycline against carbapenem resistant Acinetobacter species (CRAB) isolated from clinical specimens of patients presenting to a Tertiary Care Hospital. 
 Methods: A total of 230 clinical samples submitted to Microbiology Lab, AIMC were included in this study. All clinical specimens were identified using the standard microbiological protocol. After the confirmation of Gram negative coccobacillary rods as Acinetobacter species, modified Kirby Bauer disc diffusion method was used to detect Carbapenem resistant Acinetobacter species. Antibiotic susceptibility to Tigecycline was checked both by disc diffusion and then MICs were determined with the help of E strips (Epsilometer test).
 Results: Out of 230 isolates of Carbapenem resistant Acinetobacter, 220(95.6%) were sensitive to Tigecycline, 3(1.3%) were intermediate resistant and 07(3%) were resistant to Tigecycline.
 Conclusion: Tigecycline has shown considerable in vitro activity against MDR (multi drug resistant) including carbapenem-resistant Acinetobacter spp. It seems to be a good treatment option for infections caused by MDR Acinetobacter. However, data to support its clinical use is still limited