This paper summarizes recent evidence on the importance of personality traits in predicting life outcomes, highlighting that standardized achievement tests fail to capture key soft skills such as personality, motivation, and perseverance, which are crucial for success in life. While achievement tests are often used to measure cognitive ability, they are not sufficient to capture the full range of skills needed for success. Personality traits, such as conscientiousness, perseverance, and sociability, are strongly associated with educational attainment, health, and labor market outcomes. These traits are not well captured by traditional measures of cognitive ability, such as IQ or grades, and are influenced by a combination of genetic, environmental, and social factors. The paper discusses the limitations of standardized achievement tests in capturing the full spectrum of skills necessary for success, using the example of the GED test, which fails to capture important personality traits that affect life outcomes. It also presents evidence from the Perry Preschool Program, which improved the lives of disadvantaged children by enhancing their personality traits, even without improving their IQ scores. The study shows that early childhood interventions can have long-lasting effects on personality and life outcomes. The paper also addresses the challenges in measuring personality traits, as they are influenced by a variety of factors, including incentives, effort, and other traits. It emphasizes the importance of considering both cognitive and personality traits when evaluating life outcomes and highlights the need for a broader framework of measurement that includes personality traits in addition to cognitive ability. The findings suggest that programs that enhance personality traits should be an important part of public policy to promote human development.This paper summarizes recent evidence on the importance of personality traits in predicting life outcomes, highlighting that standardized achievement tests fail to capture key soft skills such as personality, motivation, and perseverance, which are crucial for success in life. While achievement tests are often used to measure cognitive ability, they are not sufficient to capture the full range of skills needed for success. Personality traits, such as conscientiousness, perseverance, and sociability, are strongly associated with educational attainment, health, and labor market outcomes. These traits are not well captured by traditional measures of cognitive ability, such as IQ or grades, and are influenced by a combination of genetic, environmental, and social factors. The paper discusses the limitations of standardized achievement tests in capturing the full spectrum of skills necessary for success, using the example of the GED test, which fails to capture important personality traits that affect life outcomes. It also presents evidence from the Perry Preschool Program, which improved the lives of disadvantaged children by enhancing their personality traits, even without improving their IQ scores. The study shows that early childhood interventions can have long-lasting effects on personality and life outcomes. The paper also addresses the challenges in measuring personality traits, as they are influenced by a variety of factors, including incentives, effort, and other traits. It emphasizes the importance of considering both cognitive and personality traits when evaluating life outcomes and highlights the need for a broader framework of measurement that includes personality traits in addition to cognitive ability. The findings suggest that programs that enhance personality traits should be an important part of public policy to promote human development.