This study attempts to find the factors, which are important for choosing the revolutionary car 'Nano' launched by one of the leading Indian automobile industry called 'Tata Motors'. The year 2009 has been significant for Indian automobile industry as numbers of new models were launched for the domestic market and also registered a significant growth in exports. The report published by Cygnus research ranked Indian automobile sector to be number one on the basis of sales growth and Profit After Tax (PAT) growth during October- December 09 over October- December 08 over other 14 manufacturing sectors. The paper considers 22 factors, which may be important in the customer decision-making process. Two approaches viz. Grey Relational Analysis and RIDIT analysis is used to rank the factors.