Thank you for your answer. It's straight to the point and useful.
If you don't mind, i am going to give you a bit of background information so you can relate better to my circumstances.
I have been separated/divorced for 4 years now and the ex wife has had the custody of our 2 children since then. My daughter is almost 9 years old and my son is almost 14 years old and they live right next door to me (100 yards). As you can see the kids are not babies anymore.
My issue is that i don't get to see the children as often or freely as i would like and they also tell me that they want to see me more.
One thing works against me and that is my job. Unfortunately, i work different days from one week to the other including weekends and long hours so i can't ask for regular days each week.
Depending on the mood of the ex wife i get to see the children sometimes and other times i can stay 2 to 4 weeks without seeing them so i am growing frustrated.
My son has recently informed me that he would prefer to live with me instead. In order to make this possible what steps or actions course should i take and which relevant organisations or authorities should i contact
Lastly, any ideas about cost and length of procedure !!