The GE/McKinsey matrix, developed in the 1970s for General Electric, is a multifactor portfolio analysis tool for strategic business units that assesses market attractiveness and business strength. It helps prioritize resources to improve business performance and is more comprehensive than the BCG matrix, though it has drawbacks such as not considering interdependencies between units and being complex to implement. Factors for both market and business attractiveness are assessed, but challenges remain in resource allocation and investment decisions.