What type of businesses require public relations and CSR the most? Why?

First of all, every business requires public relations so long as it has a prouct that its target audience is the public. The lubricant for every business success is the public relations orientation. 

Businesses that require public relations and corporate social responsibility the most are both public and private limited liability companies. There are codes of ethics guiding the operations of such corporate organisations one of which is giving back to society part of the benefits derived from that same environment.

All business man required his PR and CSR build just like a goodwill for a long time period for the larg organization or mid size of organization its my point of view many ideas are collect from market and marketing so marketing is not easy thing are work so only business is a cool work many ideas from market customer demand and supply and consumer give a very good ideas for business man he know about the prodct consumer and customer use it .....

All type of business require PR as they build brand as well keep company's image unsullied. CSR is a way company benefits along with befeting the society. It is that something extra that company does to improve the local and global environment/community. CSR improves public image of the company, boosts  employee involment, attract investors and retain customers as well get increased media coverage . 

All type of businesses should have a PR and CSR especially large & Mid-size companies. PR is important to enhance the company image, deliver the right information, and most importantly to connect the company with the public. CSR is essential for any profit company to lunch programs, initiatives in order to help the society and play a role to improve the lives of those with limited privileges.

All of them because you are dealing with people.

I am sure that all companies should have public relations and CSR.

All kind of companies that need to have success

Any of the businesses having their own Brand they will gain brand equity among the customer.It will show up /leverage your brand to next level and the communication of the brand delivers the best to the Customer/Consumer.

All types of private and public institutions need to have the Public Relations division or department for well promoting these institutions and facilitste their works on all levels.

Social Media.  It is inexpensive and any marketer can filter to the finest level the category of the niche he/she is trying to reach

There is no company with no public relations

Because public relations are fundamental to the organizational structure of institutions

It follows the workers and organizes the work, which is the link between the administration and the employees of the institution

And this is one of the most important roles and is responsible for improving the image of institutions and follow-up of other institutions that are similar to the institution