The most effective approach to ensure compliance with different countries' privacy and data laws is to adopt a robust data inventory and retention policy. This policy allows the company to keep a clear record of what data it has, where it is stored, and how long it should be retained according to each jurisdiction's legal requirements. By systematically categorizing data and its lifecycles, the company can tailor its compliance strategy region by region, adequately addressing the nuances of local privacy laws. Though establishing organizational policies and awareness training are beneficial, they are supplementary measures and don't directly manage data handling practices as per legal requirements. Similarly, engaging with third-party auditors can identify risks but doesn't inherently maintain compliance with varying international regulations.