Interviews with 37 branch level managers in the australian federal government were conducted to determine how managers understood the concept of innovation and their familiarity with different types of innovations. A follow-on survey found that 91% of branches introduced an innovation in the previous two years. This high rate suggests that many of the innovations could be minor. Extensive cognitive testing found that public sector managers can provide high quality estimates of the amount of person months expended on innovations and on other measures of the significance of an innovation. Using this information, the share of branches that introduced a significant innovation is approximately 60%. Although suggestive, there is no statistically significant difference in the time required to develop innovations derived from ideas provided by upper management or by lower level staff. These and other results are relevant to the design and interpretation of public sector innovation surveys.