New Delhi, Oct. 28 -- As the Big Four expand beyond traditional audit into higher-margin advisory services, mid-tier global firms are carving out their own niches. US-based Eisner Advisory Group LLC, which positions itself as one of the largest assurance providers outside the Big Four, is betting on cybersecurity, internal audit, and cross-border tax advisory for Indian startups expanding into the US. Its global capability centre (GCC) in India generates 23% of global revenue.

In an interview, chief executive Charles Weinstein also spoke to Mint about reverse listings, the firm's rollout of 11 homegrown AI tools for assurance, and why the billing model of professional services is headed for a radical change.

The advisory areas where we ...