Tally has a very customisable security system. You can set up Security Levels and users who are placed at these levels. The authority levels or Types of Security decides the rights of the users while using Tally.

I attach herewith some basic steps on implementing a security system. The system is very roles based and hence more customizable on roles rather than on vouchers. 
 
To create Security Levels

Go to Gateway of Tally, select F3: Cmp Info. > Create/Alter Company   

 In the Company Creation screen set Use Security Control to Yes.

 Enter the Name of the Administrator.

 Enter your Password and reenter the password for verification. The password is not displayed for security reasons.

 Accept Yes to save the changes made.

Types of Security (security or authority levels)

Tally has two default Security Levels. One is Owner and the other Data Entry. Owner has full access and rights to all features of Tally, except Tally Audit & Company Alteration screen, which are reserved for the Administrator alone. Data Entry has restricted rights. You are allowed to create other security levels based on these pre-defined types and allow or restrict rights as required.

Create a New Security Level
You can create New Security Levels and define task wise access rights. To create New Security Level:

Go to Gateway of Tally, select F3: Cmp Info. > Security Control> Types of Security

The Security Levels screen is displayed as shown below:

The Level Definition Screen


 A brief description on all the fields in the Level Definition screen follows:

Name of security level
This defaults to the name you have created.

Use Basic Facilities of

The default is Owner. You can select the other option Data Entry from the Security List. If the

company has other user defined Security Levels, these are also displayed in the Security List. The new level created will be available in the Security List the next time you create a Security Level.

Days allowed for Backdated vouchers
This is the number of days the users of this Level are allowed to create backdated vouchers. Specifying 0 will indicate that back-dated vouchers are not allowed, and 7 will allow the user at this level to insert vouchers going back 7 days.

Cut-off date for Backdated vouchers.
Specify the date before which users of this Security Level may not create or alter vouchers. This is additional control over and above the previous Days allowed for Backdated vouchers. This is useful in cases where you have completed your Tax Assessment for a period and no changes are desired in the data for that period.

Disallow the following facilities/Allow the following facilities
The screen is now divided into two broad columns each having two sub-columns. The left side of the screen is to disallow access to the various options of Tally. The right side allows the Security Level access for the different options.

When the cursor is on an access rights filed, the Type of Access list is displayed. Select an option from the list. The options sought to be controlled like Accounts Masters, Balance Sheet etc. are on the right (the second column from the left)

To disallow access to different options, first select the type of access from the Type of Access list. Then select the reports for which the access rights are restricted from the List of Reports. Repeat the procedure till you have set access rights for different reports. When you select a type of access, this type of access would be restricted for the corresponding report selected. For E.g if you select Full Access for Balance Sheet, the user will not have any access to Balance Sheet by this security level.

Conversely, under Allow the following facilities, if you select Full Access for Balance Sheet, the user will have full access.

Select [End of List] at the Type of Access field to complete the process.

You are taken back to the screen Security Levels for Company at a blank field following the one you just created. To create the next level, type the name and follow the same procedure. Otherwise press Enter key at the blank field and Accept, Yes to save