Unions had a great impact on working policies over the years, and, for that, I am very grateful.
However, the current Unions, mainly the ones from the public sector, in my country (Portugal) really disgust me, and I am talking from an 'employee' standpoint.
Nowadays, our Unions have a place at the government, the current party could not have a majority at the elections, so they've kind of formed a joint party with the communist and the far left party (lucky us...) in order to attain majority. The problem is that the Unions control the Communist party, so, they are now able to have a say on important decisions.
The 'heads' of these unions live at the expense of the money coming from the associates. As anyone can imagine, the cash flow is not insignificant, so, in order to maintain it, they must keep the associates happy, and are now in a position to obligate the government to meet their demands.
This should be a good thing, at least on paper; however, some things should be noted. Our country entered a huge crisis in 2008 (as so many other countries), and we ended up needing aid from the IMF. The situation was indeed, severe. In addition, we have way too many people working for the public sector (and this is not just an opinion).
Before this joint party, we were on the path of recovery, with a lot of strict measures I admit, but we were getting there. For instances, there were some companies that were being semi-privatized, companies that were causing severe deficit for the public accounts. The deals were already signed, and even, for some contracts, the payments had already been made. When the new party started functions, the Unions were able to make the new government cancel all the contracts, only because the workers (the public workers) were against this semi-privatization.
Also, we are now having a lot of strikes, with demands that, in my opinion, are completely ridiculous. For instances, in the public transport sector we are having like two strikes a month, imagine the burden that is for people that relies on public transportation to go to work, fortunately, thats not my case. And, it is important to notice that, the great majority of the demands come from people that earn way more than the minimum wage.
The government keeps on meeting the demands, at least on some degree, and guess who ends up paying for this .. New taxes are being created, and this is completely unsustainable. I fear that we end up needing external help once again.
Well, that is just my 2 cents, and I do not want to generalize my opinion to all Unions around the world, but, for the Portuguese case, I really think that the Unions are ruining the economy.