BACKGROUND Despite the evidence on anomalous attachment patterns, there has been a tendency to interpret most of these as reflecting differences in security/insecurity. METHODS Empirical research findings are reviewed in relation to attachment/insecurity as evident in both infancy and later childhood, disorganised attachment, inhibited attachment disorder, and disinhibited attachment disorder. FINDINGS Substantial differences are found in the correlates and meaning of these different features, as well as in the patterns associated with conditions such as autism, psychopathy, and Williams syndrome. CONCLUSIONS It is seriously misleading to view all of these patterns through the lens of security/insecurity. This heterogeneity in social relationship features necessarily has implications for the assessment measures for social relationships that need to be used.