Once the meditator achieves a strong and powerful concentration (jhāna, Sanskrit ध्यान dhyāna), his mind is ready to penetrate and gain <answer>insight</answer> (vipassanā) into the ultimate nature of reality, eventually obtaining release from all suffering. The cultivation of mindfulness is essential to mental concentration, which is needed to achieve <answer>insight</answer>.
Mindfulness is essential to concentration, which is neede to achieve what?
insight