Examining children's dream development is a significant challenge for researchers. Results from studies on children's dreaming may enlighten us on the nature and role of dreaming as well as broaden our knowledge of consciousness and cognitive development. This review summarizes the main questions and historical progress in developmental dream research, with the aim of shedding light on the advantages, disadvantages and effects of different settings and methods on research outcomes. A typical example would be the dreams of 3 to 5 year-olds: they are simple and static, with a relative absence of emotions and active self participation according to laboratory studies; studies using different methodology however found them to be vivid, rich in emotions, with the self as an active participant. Questions about the validity of different methods arise, and are considered within this review. Given that methodological differences can result in highly divergent outcomes, it is strongly recommended for future research to select methodology and treat results more carefully.