Share-price responses to 95 announcements of increased research and development (R & D) spending are significantly positive on average, even when the announcement occurs in the face of an earnings decline. High-technology firms that announce increases in R & D spending experience positive abnormal returns on average, whereas announcements by low-technology firms are associated with negative abnormal returns. Further, in our cross-sectional analyses we find that higher R & D intensity than the industry average leads to larger stock-price increases only for firms in high-technology industries.