The Contract Labour Act 1970 aims to prevent the exploitation of contract workers in India. It applies to establishments employing 20 or more contract laborers and requires both the principal employer and contractor to fulfill obligations like providing wages, benefits, and safe working conditions. The principal employer must obtain a certificate of registration from the appropriate government, while the contractor needs a license. Both are responsible for complying with the Act and ensuring the welfare of contract workers. Failure to do so can result in penalties and legal liabilities for the principal employer and contractor.