This note forms Part I of an eleven‑part series on the formation of contracts under English law and introduces the foundational concept of agreement, with a focus on offer and acceptance.

The note begins by explaining why contracts exist as a legal construct, before examining how agreement is established in law. It provides a structured overview of the core principles governing offer and acceptance, supported by key authorities and statutory context, and is designed to build a clear conceptual foundation for later, more detailed analysis.

Prepared with an exam‑focused approach, this resource is intended to support undergraduate and postgraduate legal study by clarifying doctrinal principles, strengthening analytical understanding, and assisting students in structuring clear and accurate answers in assessments.

This note is suitable for:

• LLB and GDL students

• LLM students requiring doctrinal refreshment

• Students preparing for UK contract law examinations

Topics covered include:

• The purpose and function of contracts in English law

• Agreement as a foundational requirement

• The legal meaning of an offer

• Acceptance and the formation of consensus

• Introductory case law on offer and acceptance

This note is designed to be read before later parts in the series, which examine invitations to treat, communication of acceptance, revocation, lapse, and certainty in greater detail.