DURING THE LAST DECADE IN AUSTRALIA, ONLY TWO STUDIES DEALT WITH A FORMAL ANALYSIS OF LONG-TERM TRENDS IN JUVENILE DELINQUENCY. THE STUDIES WERE LIMITED TO MALE JUVENILE DELINQUENTS IN NEW SOUTH WALES; IT IS NOT KNOWN IF THE FINDINGS REPRESENT DEVELOPMENTS IN OTHER AUSTRALIAN STATES. THE FINDINGS INDICATE THAT DURING THE PERIOD 1959 THROUGH 1969, THE RATES OF SIX MAJOR TYPES OF NONCAPITAL OFFENSES COMMITTED BY YOUNGER AGE GROUPS OF JUVENILES HAVE NOT INCREASED RELATIVE TO THE RATES OF THE OLDER AGE GROUPS. OF THE SIX TYPES OF OFFENSES, ONLY THE RATES OF ASSAULT OR MALICIOUS DAMAGE HAD A STATISTICALLY SIGNIFICANT UPWARD TREND. A SIGNIFICANT INCREASE IN STEALING, ASSAULTS, AND MALICIOUS DAMAGE OFFENSES AMONG 16 AND 17 YEAR OLDS IS SHOWN, WITH A DECREASE OF SEX OFFENSES WITHIN THE SAME GROUP (INCLUDING 15 YEAR OLDS). THE HIGHEST STATISTICAL SIGNIFICANCE WAS ATTACHED TO THE DECLINE OF MOTOR VEHICLE THEFT AND SEX OFFENSES AMONG 16 AND 17 YEAR OLDS, ALONG WITH THE INCREASE OF MOTIVELESS VIOLENT OFFENSES AGAINST BOTH PERSON AND PROPERTY IN THE 16-17 AGE GROUP. A 1959 TO 1970 STUDY OF TRENDS IN CHILDREN'S COURT POLICY IN NEW SOUTH WALES REVEALS A DECREASE IN INSTITUTIONALIZATION AND SUSPENDED COMMITTALS, EXCEPT FOR STEALING, ASSAULTS, AND MALICIOUS DAMAGE. THE COURT ORDER 'ADMONISHED AND DISCHARGED' HAS BEEN USED INCREASINGLY IN RESPECT TO ALL OFFENSES EXCEPT ROBBERY. THE IMPOSITION OF FINES HAS ALSO BEEN INCREASING ON ALL OFFENSES EXCEPT ROBBERY AND ASSAULT OR MALICIOUS DAMAGE. THESE STUDIES REVEAL THAT THE DECREASING PUNITIVENESS OF THE COURT HAS NOT AFFECTED THE JUVENILE CRIME RATES, EXCEPT IN THE SPECIFIC OFFENSES OF ASSAULT OR MALICIOUS DAMAGE. IN EXAMINING THE RELATIONSHIP OF URBAN ECOLOGY TO JUVENILE DELINQUENCY, THE NEW SOUTH WALES STUDIES FOLLOWED THE ANALYTICAL MODEL THAT ELUCIDATES THE LATENT ECOLOGICAL FACTORS RATHER THAN FACTORS RESPECTING THE SPATIAL DISTRIBUTION OF DELIQUENCY IN RELATION TO RECOGNIZED URBAN CHARACTERISTICS. FINDINGS INDICATE THAT IN THE METROPOLITAN AREA OF SYDNEY, THE BULK OF DELINQUENCY (83 PERCENT) IS ASSOCIATED WITH EITHER OF TWO FACTORS: (1) INDIVIDUAL-SOCIAL-ECONOMIC ALIENATION, DEFINED BY THE CLUSTERING OF ADVERSE PERSONAL AND SOCIAL CONDITIONS; AND (2) LOW SOCIOEDUCATIONAL STATUS, DEFINED BY THE CLUSTERING OF ADVERSE LOWER-CLASS CHARACTERISTICS. FOOTNOTES ARE PROVIDED. (RCB)