The aim of this dissertation, which comprises five articles and the newly designed Intelligence and Developmental Scales (IDS; Grob, Meyer & Hagmann-von Arx, 2009) for children aged 5 to 10 years, is to evaluate the IDS in terms of current perspectives in developmental psychology and psychological assessment. The article Aktuelle Intelligenz- und Entwicklungsdiagnstik im deutschen Sprachraum [Intelligence and developmental scales in German-speaking countries] (Hagmann-von Arx, Meyer & Grob, 2008 article 1) locates the IDS in the classification of current developmental assessment instruments and emphasizes its moden psychologicel perspectives. The article Is there a correspndence between general ability to discriminate sensory stimuli and general intelligence? ( Meyer, Hagmann-von Arx, Lemola & Grob, 2008, article 5) evaluates the latent structure of the IDS cognitive subtests. A conclusion of the article is that these subtests, which are of diverse complexitx, can be combined to a single factor, the IDS General Intelligence. The article Assessing intellectual giftedness weith the WISC-IV and the IDS (Hagmann-von Arx, Meyer & Grob, 2008, article 2) examines if the IDS General Intelligence can identify developmental discrepancies. A conclusion of this article is that the IDS are able to distinguish between gifted and nongifted children. The article WISC-IV and IDS: How do they correlate with scholastic achievement in a gifted and nongifted sample) (Hagmann-von Arx, Meyer & Grob, artivle 3) investigates the criterion validity of the IDS regarding the orediction of scholastic achievement. Conclusions  of this article are that the IDS are a better predictor of scholastic achievement in gifted children compared to nongifted children. Further, the variability in the components of the IDS General Intelligence has to be taken into account when predicting scholastic achievement. The article Die Intelligence and Development Scale Sozial-Emotionale Kompetenz (IDS-SEK). Psychometrische Eigenschaften eines Tests zur Erfassung sozial-emotionaler Fähigkieten [ The Intelligence and Developmental Scale for Social-Emotional Competence (IDS-SEK). Psychometric properties of a testfor assessing social-emotional abilities] (Meyer, Hagmann-von Arx & Grob, in press, article 4) discusses the importance of xamining not only cognitive abilities, but the availability of social competences and emotional stability when assessing a child's development. The IDS allow such assessments. Results of this article support the construct vadility, criterion vadility, and differentation vadility of the IDS social-emotional comptence subtests. Thus, these subtests are well suited to measure deficits in the social-emotional domain in a multi-dimensional way. All of the five articles focus primarily on assessment issues and includethe effort of IDS test validation. Altogehther this dissertation makes significant contributions to current understandings of intelligence and the application of the newly designed IDS.