HIV testing is an important public health strategy and collection of HIV testing data is a component of overall HIV surveillance activities. This paper describes changes in HIV testing patterns in relation to HIV diagnoses in Victoria between 1984 and 2004. HIV testing and diagnosis data were extracted from surveillance databases maintained at the Burnet Institute. The annual number of HIV tests performed in Victoria increased from 2,879 in 1984, to 193,927 in 2004. Between 1991 and 2004, the male HIV testing rate per 100,000 population increased from 2,754 to 3,710 and the female rate from 2,395 to 4,453. The proportion of HIV tests conducted by private laboratories increased from less than 1 per cent in 1991 to 75 per cent in 2004. The number of HIV diagnoses increased from 140 in 1999 to 233 in 2002 and then fell to 217 in 2004. The HIV diagnosis rate per 100,000 tests increased from 98.9 in 1999 to 137.7 in 2000 then decreased to 111.9 in 2004. The overall rate of HIV diagnosis per 100,000 tests was 291.6 for males and 25.9 for females. Increased testing among males is a good outcome considering the majority of HIV diagnoses in Victoria are among men who have sex with men (MSM). Increased testing among females probably relates to increased antenatal screening. The inability to collect sexual orientation and reason for test data limited interpretations. To provide a better understanding of the impact of testing on the HIV epidemiology, especially among MSM, linked HIV sentinel surveillance has been implemented in Victoria.