Although most dimensional theories of personality assume that the same traits can be assessed in either ratings or self-reports, joint factor analyses of data from these 2 methods have provided lititlee clear evidence to support this position. Previous analyses have found a preponderance of within-method factors, have had to transform variables, or have used unorthodox rotational procedures to control the effects of method variance. The present paper argues that recent conceptual and technical advances make it possible to show joint factors at the 2nd-order level using standard factor techniques. The NEO (Neuroticism, Extraversion, and Openness to Experience) Inventory and Rating Form, which measure 18 traits, were administered to 281 men and women, aged 21-89 yrs. Varimax rotation of 3 principal components showed the hypothesized structure within and across self-reports and spouse ratings. Convergent and discriminant validity of the joint factors with the Eysenck Personality Inventory scales was also shown. Results suggest that the effects of method variance can be minimized if well-qualified raters use psychometrically adequate instruments to provide ratings of clearly conceptualized traits. In addition, they provide evidence for the validity of the proposed 3-domain model of personality.