Step 1: Recall the legal requirement:
The Indian Partnership Act, 1932 does not make a written partnership deed mandatory — an oral agreement is legally just as valid.
Step 2: Why a written deed is still used in practice:
Most firms still prepare a written deed to avoid future disputes over profit-sharing, capital, interest, and duties, but the Act itself never compels it.
Final Answer:
Preparing the agreement in writing is Voluntary.