Nothing was returned from render. This usually means a return statement is missing. Or, to render nothing, return null. ``` class Board extends React.Component { renderSquare(i){ return <Square value={i} /> } render() { <div> <div> {this.renderSquare(0)} </div> </div> } } ``` ``` class Board extends React.Component { renderSquare(i){ return <Square value={i} /> } render() { return ( <div> <div> {this.renderSquare(0)} </div> </div> ) } } ```