I might write with a confident style but please don’t let that confuse you; Whilst I am a qualified Instructor and Coach, I'm not a professional climber or mountaineer so please don't take the blog post below as an authoritative guide. It’s a means of sharing my experiences and thoughts as I progress on my journey in the climbing and outdoor world and I hope they might be of help to you.

10-second summary:

• Lead climbing involves clipping the rope to the wall as you climb rather than it being attached to the top fo the route.

• The advantages of leading are that it will open up a new range of climbing experiences, including the outdoors, as well as more climbs indoors.
• The disadvantage of leading is that it does contain more risk, you need to buy more gear.
• Leading is far more common outdoors so developing leading indoors will help the transition to outdoor independence easier.
• There is typically no 'assessment' for lead climbing, but getting it wrong can have serious consequences so you may want to seek out instruction. 
• Leading brings lots of new experiences to climbing but its best to build up your new skills slowly and let them bed in to avoid developing a fear of falling. 

What is lead climbing?

In simple terms, lead climbing is where you start your climb with the rope attached to you but not attached to the wall. As you climb up you clip the rope into runners or quickdraws (carabiners on sling tapes attached to the wall). When you reach the top you clip into a carabiner (or 2) and then you lower down as you normally would. So why would you want to lead climb?

Advantages

• Most centres won't have top ropes on all of their climbs. Some climbs can be inappropriate to climb using a top rope, especially those that are steep and overhanging. Being able to lead will open these up to you.
• Leading can feel like a more authentic form of climbing as you don't have a top rope giving assistance inadvertently or otherwise and you also don't have a rope hitting you in the face all the time!
• Learning to lead climb involves improving all aspects of your technical practice so this can be a great way to improve in general. 
• Lead climbing will effectively double the types of experience you have on routes. Leading ‘feels’ different and comes with a different set of rewards when completing a lead climb.
• Lead climbing creates a closer bond between both climate and belayer.
• Provided you have a climbing partner who leads, most routes can be converted from a lead climb to a top rope by clipping 2 (or more) carabiners at the top.

Disadvantages

• The main downside to leading is the risk of falling and more specifically the fear this can create. Not only can falls be dangerous to your health but they can also be by damaging to your confidence.
• Lead belaying requires a higher level of skill than top rope belaying. I'd be happy for most people to top rope belay me but I am more selective about who I will allow to lead belay for me.
• Learning to lead is an additional cost, as is the purchase of a rope. So leading will add a little bit of cost to your Climbing. It’s a slippery slope.
• Rope buying can be a bit of a minefield, especially if you don't seek out instruction. This isn't because ropes are difficult to buy but you need to have a basic understanding of the type of rope that is best suited for your leading use cases and its suitability for use with your chosen belay device. The range and variety of belay devices have grown significantly over the past decade.

Outdoors vs. Indoors

One of the big differences between the outdoors and the indoors is leading. Indoors you don't really need to lead climb if you don't want to. Depending on the wall this might limit your access to climbs but if you have a climbing partner who does lead, they can always put a top rope up for you. Outdoors can become more challenging if you want to be independent. Outdoor sport leading and especially leading trad routes is a larger topic and requires its own article, but knowing how to lead indoors will make the process easier.

On outdoor sport routes, you almost certainly need someone who can lead to put a top rope up. In some areas you can set up a top rope from above (BUT this can be dangerous without appropriate knowledge of how to rig and stay safe). For Trad routes, you'll need the appropriate knowledge of how to set up a top rope anchor and consideration for access to the top of the route. You will also need the equipment to be able to do this including, but not limited to, passive protection, carabiners, and static and dynamic ropes. In both cases not really something you want to be doing unless you really know how to. 

Given outdoor routes can be a lot longer than indoor routes, setting up a top rope could take quite a bit of time. Also outdoors you will only get 1 route out of the rope as routes don't contain multiple climbs as they can do indoors.

In both cases operating at the top of a rock face comes with its own risks. In some cases leading to put a top rope up or leading routes may actually be less risky.

Learning

A lot of people try and learn to lead on their own. I don't know why this is, but a lot of climbers come to leading having been climbing top rope for a while and for whatever reason think they can learn on their own. When I first started leading I did the same. In retrospect, this was madness! It highlighted a lack of maturity and understanding of the risks involved with leading. It was only when I went on a learn-to-lead course with my partner that it revealed how little I knew about the risks of lead climbing and how many errors I was making without knowing it!

Typically the cost of learning to lead is the same as a beginner's course. If you compare the content and development you get out of this it's far greater than a beginner's course. Almost everyone will do a beginner's course without thinking about the cost because they want to be able to climb. If you view learning to lead as similar, ie that you’re a beginner to leading, then do yourself a favour and get an instructor who knows what they doing to teach you to lead. It might cost a bit of money but could save elsewhere! At around of £90 for 3 sessions (4-5 hours)  learning to lead costs about the same a couple of physio sessions…

Opportunities

If you do choose to lead then it's really worthwhile taking the time to allow your newly acquired skills to bed in. In general, this means dropping the difficulty of your climbing significantly to allow you the headspace and time to get used to and practise your new skills without creating undue stress or risk. This is the easiest way to mitigate the risk of a fall, especially a bad fall - take time to get skilled. Also by staying relaxed when you’re leading, you can avoid building up a fear of falling - a stealth killer of progression and fun in lead climbing. 

One of the major soft skills that has to be developed in lead climbing that you don't really need in top roping is judgement. Where should I clip from? Where can I best position myself to protect my climber? Should I top rope this climb first? How much rope will I need to give my climber? Can I fall safely here? These are all forms of the dynamic assessments and judgements you have to make when lead climbing. Maintaining an active sense of judgement about risk versus your desire to lead a climb. If it looks or feels a bit spicy there is nothing wrong with down climbing and pre-clipping or even top roping a climb first until you are comfortable leading it.

Closing thoughts

Learning to lead is an excellent way to expand the experiences you can have in climbing but is far from an obligatory one. It won't stop you from climbing hard but it may limit the range of climbs you have access to and limit the wider emotional and intellectual experience you gain from climbing.

Learning to lead doesn't mean that top roping is redundant, far from it. Top roping still has a very valid role in allowing you to try your hardest climbs or climbs where you don't want to take a risk or that you want to top rope first before leading.