Question: At the time of writing this question, the [Turkish referendum](https://en.wikipedia.org/wiki/Turkish_constitutional_referendum,_2017) for changing the Constitution has just finished with approval of these changes (about 51% for "Yes").

According to [this source](https://www.pri.org/stories/2016-07-19/over-50000-people-reportedly-arrested-or-fired-turkeys-coup-attempt), Turkish government has operated tremendous changes after the failed military coup:

> 
> Here are some more startling numbers, according to the BBC: 6,000
>  military personnel arrested, including more than two dozen generals
>  awaiting trial; 9,000 police officers fired; almost 3,000 judges
>  suspended; and more than 250 members of Prime Minister Binali
>  Yildirim's staff removed from their posts, as have 1,500 Finance
>  Ministry employees.
> 
> 
> 

So, from a layman's perspective Erdogan and his Government already have immense power, as they operated a lot of changes in key positions. So, even without a presidential system, Erdogan's will prevailed.

**Question: what is the purpose of such a referendum, if the power was already concentrated in Erdogan's and his Government's hands (or at least it looks like this)?**

Answer: 
Yes, as the Office of the President is largely ceremonial now. In this referendum, there are a few notable changes to the constitution that will give the President more **official powers** as seen below.

1.
--

The **existing parliamentary system of government will be replaced with an executive presidency and a presidential system**. This means that the office of the Prime Minister will be abolished, thus giving more authority to the President in deciding the policies of the country.

2.
--

The President will be given more authority over Supreme Board of Judges and Prosecutors appointments.

3.
--

Also, the incumbent President can now hold the office until 2029, with 1 more 5-year term compared to currently.

---

This graphic [published in CNN summarised](http://edition.cnn.com/2017/04/16/europe/turkey-referendum) everything that's changed:

[![Image](https://i.stack.imgur.com/8ztgS.jpg)](https://i.stack.imgur.com/8ztgS.jpg)

In conclusion, the President will hold executor powers instead of the Parliament if this referendum passes.
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For Erdogan, it doesn't really affects much. Because the PEOPLE, more than half supports HIM. So he wins ANY kind of election or referandum and probably he will.

Practically he chose the prime minister and the all cabinet and the all parliament (of ruling party). And even he choses the (his party's) candidates of Mayors for each city. 

For example he decided to change the prime minister (Ahmet Davutoğlu), and Mr. Davutoğlu resigned, then Binali Yıldırım is selected (as Erdoğan wants). And Ahmet Davutoğlu became prime minister with Erdoğan's will too. Davutoğlu also knows that people didn't vote for directly him but Erdoğan when he is selected on 1st of November 2015.

BUT there will be 2 changes.

1. Some of his practices are not legal (he had to be unbiased among political parties as the president but he obviously was not). Became legal.
2. More importantly, after Erdogan (at most 15 years later) there will be no leader such him. And coalition in cabinet never gave good results in Turkey. New Constitution will prevent some kind of uncertainty.

So I think the referandum for after Erdoğan.