A Power BI development company can ensure data security by implementing robust encryption, both at rest and in transit, to protect sensitive information. Employing row-level security (RLS) ensures that users only access data relevant to their role. Using secure cloud infrastructure, such as Microsoft's Azure services, guarantees compliance with industry standards. The company should also integrate with identity management systems like Azure Active Directory for role-based access and multi-factor authentication. Regular audits of data flows, adhering to GDPR and other data privacy regulations, further ensure data security for clients.