Anthropogenic environmental stressors are rapidly becoming ubiquitous across environmental systems. Effects in the initial exposed generation have been shown to directly affect fitness (either positively or negatively) in the following generation, as well as a myriad of sub-lethal effects that may in turn affect reproduction and survival, e.g. behaviour. Recent research highlights possible epigenetic (non-genetic) mechanisms as a key step in the transmission of environmental information, via germ cells, from one generation to the next. Zebrafish (Danio rerio) is a model organism frequently used in developmental biology, toxicology, genetic and behavioural studies, and thus makes an ideal candidate to investigate intergenerational and transgenerational effects in a controlled environment. More importantly the collective methylation pattern (methylome; an epigenetic modifier) is shown to be inherited via sperm. Here I investigate how differing levels of atrazine (a common herbicide and endocrine disruptor) exposure at common environmental levels during juvenile development influences the behavioural phenotype (personality traits; aggression, exploration, activity and anxiety/stress responses) of subsequent generations. We also aim to investigate whether alterations in behaviour are underpinned by changes in gene expression.