Our threshold differs from craswell et al. (1995) who classify auditors as specialists if the industry has at least 30 clients and the auditor's market share of fees and/or proportion of clients equals or exceeds 10 percent of the industry. However, the distribution of audit fees and clients in Hong Kong make these criteria impractical. When applied to the Hong Kong audit market, these criteria results in 83 percent of the clients in the three largest industries being audited by specialists. When non-Big 6 clients are excluded, this proportion increases to 97 percent leaving almost no variation in the variable of interest.