The hypothesis was tested that increase in the official crime rate is related to major demographic fluctuations such as the postwar 'baby boom,' and specifically, to both absolute and relative increases in those segments of the population which have high a priori crime rates. Crime data were collected from a Statistics Canada annual publication for the Years 1957 to 1973. The total of all criminal Code convictions was used as an indicator of the annual amount of official crime. Matching population data broken down by age and sex were obtained from the Population Estimates and Projections Division of Statistics Canada. Only data pertaining to adults aged 18 and over were used. The analysis of the population structure and crude crime rates, and of the age structure effects showed that in many respects Canadian conviction rates paralleled those of many other Western, industrialized nations. There was an overall increase in the conviction rate in the late 1950's, throughout the decade of the 1960's, and the late 1970's. A significant proportion of the increase was due to the upsurge in official female criminality as well as to overall increases in the population. Both male and female rates showed a major perturbation to their overall trends in the period of the late 1960's and the early 1970's. This should probably be attributed to the social unrest and intergenerational conflict of values which spilled over from the U.S. civil rights and anti-Vietnam war movements. However, the major hypothesis suggesting that age structure fluctuations had a significant impact on the overall growth in the crime rate was not supported. Although the Canadian age pyramid showed the ideal transition to illustrate the hypothesis with steady increases in the proportion of individuals in the very high and very low crime prone age ranges, there was very little concurrent fluctuation in the overall crime rate. Individual years could be singled out to illustrate the apparent impact of age structure, but there was no systematic trend. Statistical data and about 20 references are included. A discussion on how to calculate standardized rates is appended.