diff --git a/src/main.rs b/src/main.rs
index 2bd7c66..e7f4bc2 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,6 @@
 mod routes;
 mod sbot;
+mod utils;
 
 use rocket::{launch, routes};
 use rocket_dyn_templates::Template;
diff --git a/src/routes.rs b/src/routes.rs
index b5ad904..88afc23 100644
--- a/src/routes.rs
+++ b/src/routes.rs
@@ -1,9 +1,10 @@
-use log::info;
+use log::{info, warn};
 
-use rocket::{form::Form, get, post, response::Redirect, uri, FromForm};
+use rocket::{form::Form, get, post, response::{Redirect, Flash}, uri, FromForm, request::FlashMessage};
 use rocket_dyn_templates::{context, Template};
 
 use crate::sbot;
+use crate::utils;
 
 #[derive(FromForm)]
 pub struct PeerForm {
@@ -11,22 +12,62 @@ pub struct PeerForm {
 }
 
 #[get("/")]
-pub async fn home() -> Template {
+pub async fn home(flash: Option<FlashMessage<'_>>) -> Template {
     let whoami = match sbot::whoami().await {
         Ok(id) => id,
         Err(e) => format!("whoami call failed: {}", e),
     };
-    Template::render("base", context! { whoami })
+    Template::render("base", context! { whoami, flash })
 }
 
 #[post("/subscribe", data = "<peer>")]
-pub async fn subscribe_form(peer: Form<PeerForm>) -> Redirect {
+pub async fn subscribe_form(peer: Form<PeerForm>) -> Result<Redirect, Flash<Redirect>> {
     info!("Subscribing to peer {}", &peer.public_key);
-    Redirect::to(uri!(home))
+    if let Err(e) = utils::validate_public_key(&peer.public_key) {
+        let validation_err_msg = format!("Public key {} is invalid: {}", &peer.public_key, e);
+        warn!("{}", validation_err_msg);
+        return Err(Flash::error(Redirect::to(uri!(home)), validation_err_msg));
+    } else {
+        info!("Public key {} is valid.", &peer.public_key);
+        if let Ok(whoami) = sbot::whoami().await {
+            match sbot::is_following(&whoami, &peer.public_key).await {
+                Ok(status) if status.as_str() == "false" => {
+                    info!("Not currently following peer {}", &peer.public_key);
+                },
+                Ok(status) if status.as_str() == "true" => {
+                    info!("Already following peer {}. No further action needed here.", &peer.public_key);
+                },
+                _ => (),
+            }
+        } else {
+            warn!("Received an error during `whoami` RPC call. Please ensure the go-sbot is running and try again.")
+        }
+    }
+    Ok(Redirect::to(uri!(home)))
 }
 
 #[post("/unsubscribe", data = "<peer>")]
-pub async fn unsubscribe_form(peer: Form<PeerForm>) -> Redirect {
+pub async fn unsubscribe_form(peer: Form<PeerForm>) ->  Result<Redirect, Flash<Redirect>> {
     info!("Unsubscribing to peer {}", &peer.public_key);
-    Redirect::to(uri!(home))
+    if let Err(e) = utils::validate_public_key(&peer.public_key) {
+        let validation_err_msg = format!("Public key {} is invalid: {}", &peer.public_key, e);
+        warn!("{}", validation_err_msg);
+        return Err(Flash::error(Redirect::to(uri!(home)), validation_err_msg));
+    } else {
+        info!("Public key {} is valid.", &peer.public_key);
+        if let Ok(whoami) = sbot::whoami().await {
+            match sbot::is_following(&whoami, &peer.public_key).await {
+                Ok(status) if status.as_str() == "false" => {
+                    info!("Currently following peer {}", &peer.public_key);
+                },
+                Ok(status) if status.as_str() == "true" => {
+                    info!("Already not following peer {}. No further action needed here.", &peer.public_key);
+                },
+                _ => (),
+            }
+        } else {
+            warn!("Received an error during `whoami` RPC call. Please ensure the go-sbot is running and try again.")
+        }
+    }
+    Ok(Redirect::to(uri!(home)))
 }
diff --git a/src/sbot.rs b/src/sbot.rs
index 2e7939d..6683afa 100644
--- a/src/sbot.rs
+++ b/src/sbot.rs
@@ -1,6 +1,6 @@
 use std::env;
 
-use golgi::{sbot::Keystore, Sbot};
+use golgi::{sbot::Keystore, Sbot, api::friends::RelationshipQuery};
 
 
 pub async fn init_sbot() -> Result<Sbot, String> {
@@ -20,3 +20,15 @@ pub async fn whoami() -> Result<String, String> {
     sbort.whoami().await.map_err(|e| e.to_string())
 }
 
+pub async fn is_following(public_key_a: &str, public_key_b: &str) -> Result<String, String> {
+    let mut sbot = init_sbot().await?;
+
+    let query = RelationshipQuery {
+        source: public_key_a.to_string(),
+        dest: public_key_b.to_string(),
+    };
+
+    sbot.friends_is_following(query)
+        .await
+        .map_err(|e| e.to_string())
+}
diff --git a/src/utils.rs b/src/utils.rs
new file mode 100644
index 0000000..a155c9b
--- /dev/null
+++ b/src/utils.rs
@@ -0,0 +1,22 @@
+pub fn validate_public_key(public_key: &str) -> Result<(), String> {
+    if !public_key.starts_with('@') {
+        return Err("Expected '@' sigil as first character".to_string());
+    }
+
+    let dot_index = match public_key.rfind('.') {
+        Some(index) => index,
+        None => return Err("could not find '.' character".to_string()),
+    };
+
+    if !&public_key.ends_with(".ed25519") {
+        return Err("hashing algorithm must be ed25519".to_string());
+    }
+
+    let base64_str = &public_key[1..dot_index];
+
+    if base64_str.len() != 44 {
+        return Err("base64 data length is incorrect".to_string());
+    }
+
+    Ok(())
+}
diff --git a/templates/base.html.tera b/templates/base.html.tera
index e10610f..47b6487 100644
--- a/templates/base.html.tera
+++ b/templates/base.html.tera
@@ -14,5 +14,8 @@
       <input type="submit" value="subscribe">
       <input type="submit" value="unsubscribe" formaction="/unsubscribe">
     </form>
+    {% if flash and flash.kind == "error" %}
+    <p style="color: red;">[ {{ flash.message }} ]</p>
+    {% endif %}</p>
   </body>
 </html>