This paper adopts Avery's 19 sustainable leadership practices derived from Rhineland enterprises as a framework to examine the sustainable business practices of Thailand's second largest financial services providers. Adopting a case study approach, multi-data collection methods included non-participant observations made during visits to the enterprise, and reference to internal and published documentation and information. In-depth interview sessions were held with 26 top management team members and employees, including CEO, president and division heads. Other stakeholders include former consultants, minority and majority shareholders, and customers. Six core sets of practices consistent with the 19 sustainable leadership practices were identified: a focus on long-term perspective, people priority, innovation, social responsibility, uncertainty and change and ethical behaviour. These core themes sharply contrast with the prevailing Anglo/US business model of short-term maximisation of profitability. Enterprises in Thailand or other less developed countries which wish to sustain their organisational success can adopt Avery's 19 sustainable leadership grid elements to examine their leadership practices and adjust them to become more sustainable.