  We present abundances of carbon and oxygen as well as abundance ratios
12C/13C for a sample of carbon stars in the LMC, SMC, Carina, Sculptor and
Fornax dwarf galaxies. The overall metallicities in these dwarf galaxies are
lower than in the galactic disc. The observations cover most of the AGB and we
discuss the abundance patterns in different regions along the AGB. The
abundances are determined from infrared spectra obtained with the ISAAC
spectrometer on VLT (R=1500) and the Phoenix Spectrometer on Gemini South
(R=50000). The synthetic spectra used in the analysis were computed with MARCS
model atmospheres. We find that the oxygen abundance is decreasing with
decreasing overall metallicity of the system while the C/O ratio at a given
evolutionary phase is increasing with decreasing oxygen abundance. keywords
Stars: abundances -- Stars: carbon -- Stars: AGB and post-AGB -- Galaxies:
dwarf -- Local Group -- Infrared: stars
