Context: Tuberculosis (TB) is among the top ten causes of mortality, and to control this growing burden of disease, it is imperative that all TB patients receive the same quality of care, based on the best evidence available. The best practices for TB as enshrined in the International Standards of TB Care (ISTC) if adhered to can expedite the efforts to control TB. Aims: The aim of the study was to evaluate the current practices for diagnosis and treatment of TB among the private medical practitioners against benchmark practices in ISTC and to assess the factors associated with adherence to ISTC. Subjects and Methods: A cross-sectional study was conducted among fifty private practitioners (PPs) of Delhi over a period of 3 months. Data collection was done using a structured pro forma, and interviews were conducted privately in the PPs’ office. The key outcome variable was the proportion of practitioners adhering to the ISTC standards of diagnosis (standards: 1–6) and treatment (standards: 7–13). Results: Among fifty practitioners, 42% were found to be adherent, while 58% were found to be non-adherent. Significant association was found between gender and any form of training/sensitization received in the Revised National Tuberculosis Control Program (RNTCP) (P < 0.05). Conclusion: As the adherence to the ISTC care among the PPs was poor, there is a need to train and give incentives to participating PPs in timely and regulated way. PPs play a key role in diagnosing and treating TB patients, and hence, timely training and orientation in RNTCP and standard treatment for TB care are essential and should be key priority areas.