diff --git a/Cargo.lock b/Cargo.lock
index d92d34c..9fe4d46 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -613,7 +613,7 @@ dependencies = [
 
 [[package]]
 name = "glados"
-version = "0.1.0"
+version = "0.1.1"
 dependencies = [
  "dotenv",
  "influx_db_client",
diff --git a/Cargo.toml b/Cargo.toml
index 2ac2a2a..75a1a68 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "glados"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 license = "MIT"
 
diff --git a/src/discord.rs b/src/discord.rs
index 22c00dc..ff6db1f 100644
--- a/src/discord.rs
+++ b/src/discord.rs
@@ -6,6 +6,9 @@
 //! - `~invite Random#1234` (not possible)
 //!   - Invite someone into the guild
 //!
+//! - `~filter Active - Linked`
+//!   - Filter members based on assigned roles
+//!
 //! - Member_add
 //!   - Notify guild about new member
 //!
diff --git a/src/discord/framework.rs b/src/discord/framework.rs
index 77d43ef..56a1c43 100644
--- a/src/discord/framework.rs
+++ b/src/discord/framework.rs
@@ -13,6 +13,10 @@ use serenity::{
     model::{channel::Message, id::UserId},
 };
 
+mod filter;
+
+use filter::FILTER_COMMAND;
+
 use crate::conf::ARGS;
 
 pub fn init() -> StandardFramework {
@@ -30,7 +34,7 @@ pub fn init() -> StandardFramework {
 
 #[group]
 #[owners_only]
-#[commands(ping, invite)]
+#[commands(ping, invite, filter)]
 struct Owner;
 
 #[group]
diff --git a/src/discord/framework/filter.rs b/src/discord/framework/filter.rs
new file mode 100644
index 0000000..4747c76
--- /dev/null
+++ b/src/discord/framework/filter.rs
@@ -0,0 +1,227 @@
+use std::collections::{HashMap, HashSet};
+
+use nom::{
+    branch::alt,
+    character::complete::{char, multispace0, none_of},
+    combinator::{all_consuming, map, opt, recognize, value},
+    multi::{many0, many1},
+    sequence::tuple,
+    IResult,
+};
+use serenity::{
+    client::Context,
+    framework::standard::{macros::command, Args, CommandResult},
+    futures::StreamExt,
+    model::{channel::Message, guild::Member, id::RoleId},
+};
+
+use crate::{
+    conf::ARGS,
+    error::{Error, Result, ResultExt},
+};
+
+#[command]
+#[description = "Filter members based on roles"]
+pub async fn filter(ctx: &Context, msg: &Message, args: Args) -> CommandResult {
+    // Assemble filter
+    let filter = match MemberFilter::parse(ctx, args.rest()).await {
+        Ok(filter) => filter,
+        Err(why) => {
+            msg.reply(ctx, "I don't understand your input").await?;
+            return Err(Box::from(why));
+        }
+    };
+    // Fetch guild members
+    let mut members = ARGS.guild_id().members_iter(ctx).boxed();
+    // Member that match our filter
+    let mut matched = vec![];
+    // Filter members
+    while let Some(member) = members.next().await {
+        // Notify about member fetching errors
+        let member = match member.log_warn("fetching guild members") {
+            Some(member) => member,
+            None => continue,
+        };
+        // Apply Filter
+        if filter.matches(&member).await {
+            matched.push(member.user.id);
+        };
+    }
+    // Assemble reply
+    let reply = matched
+        .iter()
+        .fold(String::from("Filtered members:"), |s, id| {
+            s + &format!(" {}", id)
+        });
+    msg.reply(ctx, reply).await?;
+    Ok(())
+}
+
+#[derive(Debug, Default, Clone)]
+struct MemberFilter {
+    add: HashSet<RoleId>,
+    sub: HashSet<RoleId>,
+}
+
+#[derive(Debug, Default, Clone, PartialEq)]
+struct RawMemberFilter<'i> {
+    add: Vec<&'i str>,
+    sub: Vec<&'i str>,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+enum Sign {
+    Plus,
+    Minus,
+}
+
+impl MemberFilter {
+    pub async fn parse(ctx: &Context, raw: &str) -> Result<Self> {
+        let raw_filter = all_consuming(parse_member_filter)(raw)
+            .map(|(_, filter)| filter)
+            .map_err(|why| Error::ParseMemberFilter(why.to_owned()))?;
+        Self::from_raw(ctx, raw_filter).await
+    }
+
+    /// Does this filter match the given member?
+    ///
+    /// # When is this true?
+    /// - If `add` is not empty:
+    ///   - `member` has a role in `add` and none in `sub`
+    /// - If `add` is empty but `sub` is not:
+    ///   - `member` has no role in `sub`
+    /// - If `add` and `sub` are empty:
+    ///   - YES!
+    pub async fn matches(&self, member: &Member) -> bool {
+        let roles: HashSet<_> = member.roles.clone().into_iter().collect();
+        if !self.add.is_empty() {
+            let add_intersection: HashSet<_> = self.add.intersection(&roles).collect();
+            let sub_intersection: HashSet<_> = self.sub.intersection(&roles).collect();
+            !add_intersection.is_empty() && sub_intersection.is_empty()
+        } else if self.add.is_empty() && !self.sub.is_empty() {
+            let sub_intersection: HashSet<_> = self.sub.intersection(&roles).collect();
+            sub_intersection.is_empty()
+        } else {
+            true
+        }
+    }
+
+    async fn from_raw(ctx: &Context, raw_filter: RawMemberFilter<'_>) -> Result<Self> {
+        let RawMemberFilter { add, sub } = raw_filter;
+        // Map role names to role ids
+        let roles: HashMap<_, _> = ARGS
+            .guild_id()
+            .roles(ctx)
+            .await?
+            .into_iter()
+            .map(|(id, role)| (role.name, id))
+            .collect();
+        // Helper to map a role name to a role id, if that role exists
+        let to_id = |name: &str| -> Result<RoleId> {
+            let name = name.trim();
+            match roles.get(name) {
+                Some(id) => Ok(*id),
+                None => Err(Error::UnknownRoleInFilter(name.to_owned())),
+            }
+        };
+        // Helper to collect a Result<Vec<_>> from results
+        let set_from_res = |mut set: HashSet<_>, id: Result<_>| -> Result<_> {
+            set.insert(id?);
+            Ok(set)
+        };
+        Ok(MemberFilter {
+            add: add
+                .into_iter()
+                .map(to_id)
+                .try_fold(HashSet::new(), set_from_res)?,
+            sub: sub
+                .into_iter()
+                .map(to_id)
+                .try_fold(HashSet::new(), set_from_res)?,
+        })
+    }
+}
+
+fn parse_member_filter(inp: &str) -> IResult<&str, RawMemberFilter<'_>> {
+    map(many0(parse_role), |roles| {
+        let mut filter = RawMemberFilter::default();
+        for (sign, role) in roles {
+            match sign {
+                Sign::Plus => filter.add.push(role),
+                Sign::Minus => filter.sub.push(role),
+            }
+        }
+        filter
+    })(inp.trim())
+}
+
+fn parse_role(inp: &str) -> IResult<&str, (Sign, &str)> {
+    let parse_sign = alt((
+        value(Sign::Minus, char('-')),
+        value(Sign::Plus, opt(char('+'))),
+    ));
+    // TODO: No whitespaces/plus/minus allowed but Discord roles allow almost any char
+    let parse_role_name = recognize(many1(none_of(" +-\t\n\r")));
+    map(
+        tuple((parse_sign, multispace0, parse_role_name, multispace0)),
+        |(sign, _, role, _)| (sign, role),
+    )(inp)
+}
+
+#[cfg(test)]
+mod tests {
+    use nom::combinator::all_consuming;
+
+    use crate::discord::framework::filter::{RawMemberFilter, Sign};
+
+    macro_rules! parse {
+        ($fn:path, $str:literal, $ok_val:expr) => {
+            let res = all_consuming($fn)($str);
+            assert_eq!(res.unwrap().1, $ok_val)
+        };
+    }
+
+    #[test]
+    fn parse_role() {
+        use super::parse_role;
+        parse!(parse_role, "test", (Sign::Plus, "test"));
+        parse!(parse_role, "-test", (Sign::Minus, "test"));
+    }
+
+    #[test]
+    fn parse_member_filter() {
+        use super::parse_member_filter;
+        parse!(
+            parse_member_filter,
+            "test",
+            RawMemberFilter {
+                add: vec!["test"],
+                sub: vec![],
+            }
+        );
+        parse!(
+            parse_member_filter,
+            "+other",
+            RawMemberFilter {
+                add: vec!["other"],
+                sub: vec![],
+            }
+        );
+        parse!(
+            parse_member_filter,
+            "-test -9+some_other\t +dis",
+            RawMemberFilter {
+                add: vec!["some_other", "dis"],
+                sub: vec!["test", "9"],
+            }
+        );
+        parse!(
+            parse_member_filter,
+            "\t -test \t\n+other",
+            RawMemberFilter {
+                add: vec!["other"],
+                sub: vec!["test"],
+            }
+        );
+    }
+}
diff --git a/src/error.rs b/src/error.rs
index 3938c2b..58ea4cd 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -24,6 +24,10 @@ pub enum Error {
     RconListCmd(#[source] nom::Err<nom::error::Error<String>>),
     #[error("Parsing results of `whois` command: {_0}")]
     RconWhoIsCmd(#[source] nom::Err<nom::error::Error<String>>),
+    #[error("Parsing member filter of `~filter` command: {_0}")]
+    ParseMemberFilter(#[source] nom::Err<nom::error::Error<String>>),
+    #[error("Unknown role {_0:?} in filter")]
+    UnknownRoleInFilter(String),
 }
 
 pub trait ResultExt<T> {
@@ -66,3 +70,23 @@ where
         }
     }
 }
+
+impl<E> ResultExt<E> for E
+where
+    E: fmt::Display,
+{
+    fn log_info(self, when: &str) -> Option<E> {
+        tracing::info!("Error occured while {}: {}", when, self);
+        None
+    }
+
+    fn log_warn(self, when: &str) -> Option<E> {
+        tracing::warn!("Error occured while {}: {}", when, self);
+        None
+    }
+
+    fn log_error(self, when: &str) -> Option<E> {
+        tracing::warn!("Error occured while {}: {}", when, self);
+        None
+    }
+}